Merge remote-tracking branch 'goog/master' into mergescriptpackage

Conflicts: java/res/values-ca/strings.xml java/res/values-cs/strings.xml java/res/values-de/strings.xml java/res/values-es/strings.xml java/res/values-hr/strings.xml java/res/values-hu/strings.xml java/res/values-it/strings.xml java/res/values-lv/strings.xml java/res/values-nb/strings.xml java/res/values-nl/strings.xml java/res/values-pl/strings.xml java/res/values-pt/strings.xml java/res/values-ro/strings.xml java/res/values-ru/strings.xml java/res/values-sv/strings.xml java/res/values-sw/strings.xml java/res/values-tr/strings.xml java/res/values-uk/strings.xml java/res/values-zh-rCN/strings.xml java/res/values-zh-rTW/strings.xml java/src/com/android/inputmethod/latin/RichInputConnection.java Change-Id: Iba00dd5b86cb16d72968bc7e40d75853845b6dcb
author: Satoshi Kataoka <satok@google.com> 2012-11-06 12:49:53 +0900
committer: Satoshi Kataoka <satok@google.com> 2012-11-06 12:49:53 +0900
commit: 555e15a96a00e8829981557d96e9fa7fc5a74f8c (patch)
tree: 9750c7af9777b63c176cc780c2a6de4849931434 /java/src/com/android/inputmethod/latin
parent: 9381ab669f12664f7e2debea846d3ce71f89b256 (diff)
parent: 5f2fa6b82cbb6714ab2996aebc16f10c62d0e673 (diff)
download: latinime-555e15a96a00e8829981557d96e9fa7fc5a74f8c.tar.gz
latinime-555e15a96a00e8829981557d96e9fa7fc5a74f8c.tar.xz
latinime-555e15a96a00e8829981557d96e9fa7fc5a74f8c.zip
69 files changed, 2220 insertions, 1255 deletions
diff --git a/java/src/com/android/inputmethod/latin/AdditionalSubtypeSettings.java b/java/src/com/android/inputmethod/latin/AdditionalSubtypeSettings.java
index ae51d2537..d12607721 100644
--- a/java/src/com/android/inputmethod/latin/AdditionalSubtypeSettings.java
+++ b/java/src/com/android/inputmethod/latin/AdditionalSubtypeSettings.java
@@ -49,7 +49,7 @@ import com.android.inputmethod.compat.CompatUtils;
 import java.util.ArrayList;
 import java.util.TreeSet;
 
-public class AdditionalSubtypeSettings extends PreferenceFragment {
+public final class AdditionalSubtypeSettings extends PreferenceFragment {
     private SharedPreferences mPrefs;
     private SubtypeLocaleAdapter mSubtypeLocaleAdapter;
     private KeyboardLayoutSetAdapter mKeyboardLayoutSetAdapter;
diff --git a/java/src/com/android/inputmethod/latin/AssetFileAddress.java b/java/src/com/android/inputmethod/latin/AssetFileAddress.java
index 3549a1561..29c733ba6 100644
--- a/java/src/com/android/inputmethod/latin/AssetFileAddress.java
+++ b/java/src/com/android/inputmethod/latin/AssetFileAddress.java
@@ -24,7 +24,7 @@ import java.io.File;
  * the package file. Open it correctly thus requires the name of the package it is in, but
  * also the offset in the file and the length of this data. This class encapsulates these three.
  */
-class AssetFileAddress {
+final class AssetFileAddress {
     public final String mFilename;
     public final long mOffset;
     public final long mLength;
diff --git a/java/src/com/android/inputmethod/latin/AudioAndHapticFeedbackManager.java b/java/src/com/android/inputmethod/latin/AudioAndHapticFeedbackManager.java
index 55664d411..024726391 100644
--- a/java/src/com/android/inputmethod/latin/AudioAndHapticFeedbackManager.java
+++ b/java/src/com/android/inputmethod/latin/AudioAndHapticFeedbackManager.java
@@ -21,7 +21,6 @@ import android.media.AudioManager;
 import android.view.HapticFeedbackConstants;
 import android.view.View;
 
-import com.android.inputmethod.keyboard.Keyboard;
 import com.android.inputmethod.latin.VibratorUtils;
 
 /**
@@ -30,18 +29,16 @@ import com.android.inputmethod.latin.VibratorUtils;
  * It offers a consistent and simple interface that allows LatinIME to forget about the
  * complexity of settings and the like.
  */
-public class AudioAndHapticFeedbackManager {
-    final private SettingsValues mSettingsValues;
-    final private AudioManager mAudioManager;
-    final private VibratorUtils mVibratorUtils;
+public final class AudioAndHapticFeedbackManager {
+    private final AudioManager mAudioManager;
+    private final VibratorUtils mVibratorUtils;
+
+    private SettingsValues mSettingsValues;
     private boolean mSoundOn;
 
-    public AudioAndHapticFeedbackManager(final LatinIME latinIme,
-            final SettingsValues settingsValues) {
-        mSettingsValues = settingsValues;
+    public AudioAndHapticFeedbackManager(final LatinIME latinIme) {
         mVibratorUtils = VibratorUtils.getInstance(latinIme);
         mAudioManager = (AudioManager) latinIme.getSystemService(Context.AUDIO_SERVICE);
-        mSoundOn = reevaluateIfSoundIsOn();
     }
 
     public void hapticAndAudioFeedback(final int primaryCode,
@@ -51,7 +48,7 @@ public class AudioAndHapticFeedbackManager {
     }
 
     private boolean reevaluateIfSoundIsOn() {
-        if (!mSettingsValues.mSoundOn || mAudioManager == null) {
+        if (mSettingsValues == null || !mSettingsValues.mSoundOn || mAudioManager == null) {
             return false;
         } else {
             return mAudioManager.getRingerMode() == AudioManager.RINGER_MODE_NORMAL;
@@ -64,13 +61,13 @@ public class AudioAndHapticFeedbackManager {
         if (mSoundOn) {
             final int sound;
             switch (primaryCode) {
-            case Keyboard.CODE_DELETE:
+            case Constants.CODE_DELETE:
                 sound = AudioManager.FX_KEYPRESS_DELETE;
                 break;
-            case Keyboard.CODE_ENTER:
+            case Constants.CODE_ENTER:
                 sound = AudioManager.FX_KEYPRESS_RETURN;
                 break;
-            case Keyboard.CODE_SPACE:
+            case Constants.CODE_SPACE:
                 sound = AudioManager.FX_KEYPRESS_SPACEBAR;
                 break;
             default:
@@ -81,8 +78,7 @@ public class AudioAndHapticFeedbackManager {
         }
     }
 
-    // TODO: make this private when LatinIME does not call it any more
-    public void vibrate(final View viewToPerformHapticFeedbackOn) {
+    private void vibrate(final View viewToPerformHapticFeedbackOn) {
         if (!mSettingsValues.mVibrateOn) {
             return;
         }
@@ -98,6 +94,11 @@ public class AudioAndHapticFeedbackManager {
         }
     }
 
+    public void onSettingsChanged(final SettingsValues settingsValues) {
+        mSettingsValues = settingsValues;
+        mSoundOn = reevaluateIfSoundIsOn();
+    }
+
     public void onRingerModeChanged() {
         mSoundOn = reevaluateIfSoundIsOn();
     }
diff --git a/java/src/com/android/inputmethod/latin/AutoCorrection.java b/java/src/com/android/inputmethod/latin/AutoCorrection.java
index f425e360a..fa35922b0 100644
--- a/java/src/com/android/inputmethod/latin/AutoCorrection.java
+++ b/java/src/com/android/inputmethod/latin/AutoCorrection.java
@@ -23,7 +23,7 @@ import android.util.Log;
 
 import java.util.concurrent.ConcurrentHashMap;
 
-public class AutoCorrection {
+public final class AutoCorrection {
     private static final boolean DBG = LatinImeLogger.sDBG;
     private static final String TAG = AutoCorrection.class.getSimpleName();
     private static final int MINIMUM_SAFETY_NET_CHAR_LENGTH = 4;
@@ -33,11 +33,11 @@ public class AutoCorrection {
     }
 
     public static boolean isValidWord(final ConcurrentHashMap<String, Dictionary> dictionaries,
-            CharSequence word, boolean ignoreCase) {
+            final String word, final boolean ignoreCase) {
         if (TextUtils.isEmpty(word)) {
             return false;
         }
-        final CharSequence lowerCasedWord = word.toString().toLowerCase();
+        final String lowerCasedWord = word.toLowerCase();
         for (final String key : dictionaries.keySet()) {
             final Dictionary dictionary = dictionaries.get(key);
             // It's unclear how realistically 'dictionary' can be null, but the monkey is somehow
@@ -57,7 +57,7 @@ public class AutoCorrection {
     }
 
     public static int getMaxFrequency(final ConcurrentHashMap<String, Dictionary> dictionaries,
-            CharSequence word) {
+            final String word) {
         if (TextUtils.isEmpty(word)) {
             return Dictionary.NOT_A_PROBABILITY;
         }
@@ -76,12 +76,13 @@ public class AutoCorrection {
     // Returns true if this is in any of the dictionaries.
     public static boolean isInTheDictionary(
             final ConcurrentHashMap<String, Dictionary> dictionaries,
-            final CharSequence word, final boolean ignoreCase) {
+            final String word, final boolean ignoreCase) {
         return isValidWord(dictionaries, word, ignoreCase);
     }
 
-    public static boolean suggestionExceedsAutoCorrectionThreshold(SuggestedWordInfo suggestion,
-            CharSequence consideredWord, float autoCorrectionThreshold) {
+    public static boolean suggestionExceedsAutoCorrectionThreshold(
+            final SuggestedWordInfo suggestion, final String consideredWord,
+            final float autoCorrectionThreshold) {
         if (null != suggestion) {
             // Shortlist a whitelisted word
             if (suggestion.mKind == SuggestedWordInfo.KIND_WHITELIST) return true;
@@ -89,8 +90,7 @@ public class AutoCorrection {
             // TODO: when the normalized score of the first suggestion is nearly equals to
             //       the normalized score of the second suggestion, behave less aggressive.
             final float normalizedScore = BinaryDictionary.calcNormalizedScore(
-                    consideredWord.toString(), suggestion.mWord.toString(),
-                    autoCorrectionSuggestionScore);
+                    consideredWord, suggestion.mWord, autoCorrectionSuggestionScore);
             if (DBG) {
                 Log.d(TAG, "Normalized " + consideredWord + "," + suggestion + ","
                         + autoCorrectionSuggestionScore + ", " + normalizedScore
@@ -100,8 +100,7 @@ public class AutoCorrection {
                 if (DBG) {
                     Log.d(TAG, "Auto corrected by S-threshold.");
                 }
-                return !shouldBlockAutoCorrectionBySafetyNet(consideredWord.toString(),
-                        suggestion.mWord);
+                return !shouldBlockAutoCorrectionBySafetyNet(consideredWord, suggestion.mWord);
             }
         }
         return false;
@@ -110,7 +109,7 @@ public class AutoCorrection {
     // TODO: Resolve the inconsistencies between the native auto correction algorithms and
     // this safety net
     public static boolean shouldBlockAutoCorrectionBySafetyNet(final String typedWord,
-            final CharSequence suggestion) {
+            final String suggestion) {
         // Safety net for auto correction.
         // Actually if we hit this safety net, it's a bug.
         // If user selected aggressive auto correction mode, there is no need to use the safety
@@ -123,7 +122,7 @@ public class AutoCorrection {
         }
         final int maxEditDistanceOfNativeDictionary =
                 (typedWordLength < 5 ? 2 : typedWordLength / 2) + 1;
-        final int distance = BinaryDictionary.editDistance(typedWord, suggestion.toString());
+        final int distance = BinaryDictionary.editDistance(typedWord, suggestion);
         if (DBG) {
             Log.d(TAG, "Autocorrected edit distance = " + distance
                     + ", " + maxEditDistanceOfNativeDictionary);
diff --git a/java/src/com/android/inputmethod/latin/BackupAgent.java b/java/src/com/android/inputmethod/latin/BackupAgent.java
index ee070af75..0beb088ac 100644
--- a/java/src/com/android/inputmethod/latin/BackupAgent.java
+++ b/java/src/com/android/inputmethod/latin/BackupAgent.java
@@ -22,7 +22,7 @@ import android.app.backup.SharedPreferencesBackupHelper;
 /**
  * Backs up the Latin IME shared preferences.
  */
-public class BackupAgent extends BackupAgentHelper {
+public final class BackupAgent extends BackupAgentHelper {
 
     @Override
     public void onCreate() {
diff --git a/java/src/com/android/inputmethod/latin/BinaryDictionary.java b/java/src/com/android/inputmethod/latin/BinaryDictionary.java
index c3ae81f3a..a7024d1d8 100644
--- a/java/src/com/android/inputmethod/latin/BinaryDictionary.java
+++ b/java/src/com/android/inputmethod/latin/BinaryDictionary.java
@@ -30,8 +30,8 @@ import java.util.Locale;
 /**
  * Implements a static, compacted, binary dictionary of standard words.
  */
-public class BinaryDictionary extends Dictionary {
-
+public final class BinaryDictionary extends Dictionary {
+    private static final String TAG = BinaryDictionary.class.getSimpleName();
     public static final String DICTIONARY_PACK_AUTHORITY =
             "com.android.inputmethod.latin.dictionarypack";
 
@@ -45,17 +45,13 @@ public class BinaryDictionary extends Dictionary {
     public static final int MAX_WORDS = 18;
     public static final int MAX_SPACES = 16;
 
-    private static final String TAG = "BinaryDictionary";
     private static final int MAX_PREDICTIONS = 60;
     private static final int MAX_RESULTS = Math.max(MAX_PREDICTIONS, MAX_WORDS);
 
-    private static final int TYPED_LETTER_MULTIPLIER = 2;
-
     private long mNativeDict;
     private final Locale mLocale;
     private final int[] mInputCodePoints = new int[MAX_WORD_LENGTH];
-    // TODO: The below should be int[] mOutputCodePoints
-    private final char[] mOutputChars = new char[MAX_WORD_LENGTH * MAX_RESULTS];
+    private final int[] mOutputCodePoints = new int[MAX_WORD_LENGTH * MAX_RESULTS];
     private final int[] mSpaceIndices = new int[MAX_SPACES];
     private final int[] mOutputScores = new int[MAX_RESULTS];
     private final int[] mOutputTypes = new int[MAX_RESULTS];
@@ -67,7 +63,7 @@ public class BinaryDictionary extends Dictionary {
 
     // TODO: There should be a way to remove used DicTraverseSession objects from
     // {@code mDicTraverseSessions}.
-    private DicTraverseSession getTraverseSession(int traverseSessionId) {
+    private DicTraverseSession getTraverseSession(final int traverseSessionId) {
         synchronized(mDicTraverseSessions) {
             DicTraverseSession traverseSession = mDicTraverseSessions.get(traverseSessionId);
             if (traverseSession == null) {
@@ -84,7 +80,6 @@ public class BinaryDictionary extends Dictionary {
     /**
      * Constructor for the binary dictionary. This is supposed to be called from the
      * dictionary factory.
-     * All implementations should pass null into flagArray, except for testing purposes.
      * @param context the context to access the environment from.
      * @param filename the name of the file to read through native code.
      * @param offset the offset of the dictionary data within the file.
@@ -92,9 +87,9 @@ public class BinaryDictionary extends Dictionary {
      * @param useFullEditDistance whether to use the full edit distance in suggestions
      * @param dictType the dictionary type, as a human-readable string
      */
-    public BinaryDictionary(final Context context,
-            final String filename, final long offset, final long length,
-            final boolean useFullEditDistance, final Locale locale, final String dictType) {
+    public BinaryDictionary(final Context context, final String filename, final long offset,
+            final long length, final boolean useFullEditDistance, final Locale locale,
+            final String dictType) {
         super(dictType);
         mLocale = locale;
         mUseFullEditDistance = useFullEditDistance;
@@ -106,40 +101,40 @@ public class BinaryDictionary extends Dictionary {
     }
 
     private native long openNative(String sourceDir, long dictOffset, long dictSize,
-            int typedLetterMultiplier, int fullWordMultiplier, int maxWordLength, int maxWords,
-            int maxPredictions);
+            int fullWordMultiplier, int maxWordLength, int maxWords, int maxPredictions);
     private native void closeNative(long dict);
     private native int getFrequencyNative(long dict, int[] word);
     private native boolean isValidBigramNative(long dict, int[] word1, int[] word2);
     private native int getSuggestionsNative(long dict, long proximityInfo, long traverseSession,
             int[] xCoordinates, int[] yCoordinates, int[] times, int[] pointerIds,
             int[] inputCodePoints, int codesSize, int commitPoint, boolean isGesture,
-            int[] prevWordCodePointArray, boolean useFullEditDistance, char[] outputChars,
+            int[] prevWordCodePointArray, boolean useFullEditDistance, int[] outputCodePoints,
             int[] outputScores, int[] outputIndices, int[] outputTypes);
-    private static native float calcNormalizedScoreNative(char[] before, char[] after, int score);
-    private static native int editDistanceNative(char[] before, char[] after);
+    private static native float calcNormalizedScoreNative(int[] before, int[] after, int score);
+    private static native int editDistanceNative(int[] before, int[] after);
 
     // TODO: Move native dict into session
-    private final void loadDictionary(String path, long startOffset, long length) {
-        mNativeDict = openNative(path, startOffset, length, TYPED_LETTER_MULTIPLIER,
-                FULL_WORD_SCORE_MULTIPLIER, MAX_WORD_LENGTH, MAX_WORDS, MAX_PREDICTIONS);
+    private final void loadDictionary(final String path, final long startOffset,
+            final long length) {
+        mNativeDict = openNative(path, startOffset, length, FULL_WORD_SCORE_MULTIPLIER,
+                MAX_WORD_LENGTH, MAX_WORDS, MAX_PREDICTIONS);
     }
 
     @Override
     public ArrayList<SuggestedWordInfo> getSuggestions(final WordComposer composer,
-            final CharSequence prevWord, final ProximityInfo proximityInfo) {
+            final String prevWord, final ProximityInfo proximityInfo) {
         return getSuggestionsWithSessionId(composer, prevWord, proximityInfo, 0);
     }
 
     @Override
     public ArrayList<SuggestedWordInfo> getSuggestionsWithSessionId(final WordComposer composer,
-            final CharSequence prevWord, final ProximityInfo proximityInfo, int sessionId) {
+            final String prevWord, final ProximityInfo proximityInfo, int sessionId) {
         if (!isValidDictionary()) return null;
 
         Arrays.fill(mInputCodePoints, Constants.NOT_A_CODE);
         // TODO: toLowerCase in the native code
         final int[] prevWordCodePointArray = (null == prevWord)
-                ? null : StringUtils.toCodePointArray(prevWord.toString());
+                ? null : StringUtils.toCodePointArray(prevWord);
         final int composerSize = composer.size();
 
         final boolean isGesture = composer.isBatchMode();
@@ -157,7 +152,8 @@ public class BinaryDictionary extends Dictionary {
                 proximityInfo.getNativeProximityInfo(), getTraverseSession(sessionId).getSession(),
                 ips.getXCoordinates(), ips.getYCoordinates(), ips.getTimes(), ips.getPointerIds(),
                 mInputCodePoints, codesSize, 0 /* commitPoint */, isGesture, prevWordCodePointArray,
-                mUseFullEditDistance, mOutputChars, mOutputScores, mSpaceIndices, mOutputTypes);
+                mUseFullEditDistance, mOutputCodePoints, mOutputScores, mSpaceIndices,
+                mOutputTypes);
         final int count = Math.min(tmpCount, MAX_PREDICTIONS);
 
         final ArrayList<SuggestedWordInfo> suggestions = CollectionUtils.newArrayList();
@@ -165,50 +161,56 @@ public class BinaryDictionary extends Dictionary {
             if (composerSize > 0 && mOutputScores[j] < 1) break;
             final int start = j * MAX_WORD_LENGTH;
             int len = 0;
-            while (len < MAX_WORD_LENGTH && mOutputChars[start + len] != 0) {
+            while (len < MAX_WORD_LENGTH && mOutputCodePoints[start + len] != 0) {
                 ++len;
             }
             if (len > 0) {
                 final int score = SuggestedWordInfo.KIND_WHITELIST == mOutputTypes[j]
                         ? SuggestedWordInfo.MAX_SCORE : mOutputScores[j];
-                suggestions.add(new SuggestedWordInfo(
-                        new String(mOutputChars, start, len), score, mOutputTypes[j], mDictType));
+                suggestions.add(new SuggestedWordInfo(new String(mOutputCodePoints, start, len),
+                        score, mOutputTypes[j], mDictType));
             }
         }
         return suggestions;
     }
 
-    /* package for test */ boolean isValidDictionary() {
+    public boolean isValidDictionary() {
         return mNativeDict != 0;
     }
 
-    public static float calcNormalizedScore(String before, String after, int score) {
-        return calcNormalizedScoreNative(before.toCharArray(), after.toCharArray(), score);
+    public static float calcNormalizedScore(final String before, final String after,
+            final int score) {
+        return calcNormalizedScoreNative(StringUtils.toCodePointArray(before),
+                StringUtils.toCodePointArray(after), score);
     }
 
-    public static int editDistance(String before, String after) {
-        return editDistanceNative(before.toCharArray(), after.toCharArray());
+    public static int editDistance(final String before, final String after) {
+        if (before == null || after == null) {
+            throw new IllegalArgumentException();
+        }
+        return editDistanceNative(StringUtils.toCodePointArray(before),
+                StringUtils.toCodePointArray(after));
     }
 
     @Override
-    public boolean isValidWord(CharSequence word) {
+    public boolean isValidWord(final String word) {
         return getFrequency(word) >= 0;
     }
 
     @Override
-    public int getFrequency(CharSequence word) {
+    public int getFrequency(final String word) {
         if (word == null) return -1;
-        int[] codePoints = StringUtils.toCodePointArray(word.toString());
+        int[] codePoints = StringUtils.toCodePointArray(word);
         return getFrequencyNative(mNativeDict, codePoints);
     }
 
     // TODO: Add a batch process version (isValidBigramMultiple?) to avoid excessive numbers of jni
     // calls when checking for changes in an entire dictionary.
-    public boolean isValidBigram(CharSequence word1, CharSequence word2) {
+    public boolean isValidBigram(final String word1, final String word2) {
         if (TextUtils.isEmpty(word1) || TextUtils.isEmpty(word2)) return false;
-        int[] chars1 = StringUtils.toCodePointArray(word1.toString());
-        int[] chars2 = StringUtils.toCodePointArray(word2.toString());
-        return isValidBigramNative(mNativeDict, chars1, chars2);
+        final int[] codePoints1 = StringUtils.toCodePointArray(word1);
+        final int[] codePoints2 = StringUtils.toCodePointArray(word2);
+        return isValidBigramNative(mNativeDict, codePoints1, codePoints2);
     }
 
     @Override
diff --git a/java/src/com/android/inputmethod/latin/BinaryDictionaryFileDumper.java b/java/src/com/android/inputmethod/latin/BinaryDictionaryFileDumper.java
index 799aea8ef..bed31a7d1 100644
--- a/java/src/com/android/inputmethod/latin/BinaryDictionaryFileDumper.java
+++ b/java/src/com/android/inputmethod/latin/BinaryDictionaryFileDumper.java
@@ -30,7 +30,6 @@ import java.io.FileNotFoundException;
 import java.io.FileOutputStream;
 import java.io.IOException;
 import java.io.InputStream;
-import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.Collections;
 import java.util.List;
@@ -40,14 +39,14 @@ import java.util.Locale;
  * Group class for static methods to help with creation and getting of the binary dictionary
  * file from the dictionary provider
  */
-public class BinaryDictionaryFileDumper {
+public final class BinaryDictionaryFileDumper {
     private static final String TAG = BinaryDictionaryFileDumper.class.getSimpleName();
     private static final boolean DEBUG = false;
 
     /**
      * The size of the temporary buffer to copy files.
      */
-    private static final int FILE_READ_BUFFER_SIZE = 1024;
+    private static final int FILE_READ_BUFFER_SIZE = 8192;
     // TODO: make the following data common with the native code
     private static final byte[] MAGIC_NUMBER_VERSION_1 =
             new byte[] { (byte)0x78, (byte)0xB1, (byte)0x00, (byte)0x00 };
@@ -150,7 +149,13 @@ public class BinaryDictionaryFileDumper {
 
         final Uri.Builder wordListUriBuilder = getProviderUriBuilder(id);
         final String finalFileName = BinaryDictionaryGetter.getCacheFileName(id, locale, context);
-        final String tempFileName = finalFileName + ".tmp";
+        String tempFileName;
+        try {
+            tempFileName = BinaryDictionaryGetter.getTempFileName(id, context);
+        } catch (IOException e) {
+            Log.e(TAG, "Can't open the temporary file", e);
+            return null;
+        }
 
         for (int mode = MODE_MIN; mode <= MODE_MAX; ++mode) {
             InputStream originalSourceStream = null;
@@ -201,6 +206,7 @@ public class BinaryDictionaryFileDumper {
                 outputStream.flush();
                 outputStream.close();
                 final File finalFile = new File(finalFileName);
+                finalFile.delete();
                 if (!outputFile.renameTo(finalFile)) {
                     throw new IOException("Can't move the file to its final name");
                 }
@@ -287,6 +293,7 @@ public class BinaryDictionaryFileDumper {
      * @param input the stream to be copied.
      * @param output an output stream to copy the data to.
      */
+    // TODO: make output a BufferedOutputStream
     private static void checkMagicAndCopyFileTo(final BufferedInputStream input,
             final FileOutputStream output) throws FileNotFoundException, IOException {
         // Check the magic number
diff --git a/java/src/com/android/inputmethod/latin/BinaryDictionaryGetter.java b/java/src/com/android/inputmethod/latin/BinaryDictionaryGetter.java
index 9764df072..ecb61b46f 100644
--- a/java/src/com/android/inputmethod/latin/BinaryDictionaryGetter.java
+++ b/java/src/com/android/inputmethod/latin/BinaryDictionaryGetter.java
@@ -37,7 +37,7 @@ import java.util.Locale;
 /**
  * Helper class to get the address of a mmap'able dictionary file.
  */
-class BinaryDictionaryGetter {
+final class BinaryDictionaryGetter {
 
     /**
      * Used for Log actions from this class
@@ -164,6 +164,13 @@ class BinaryDictionaryGetter {
     }
 
     /**
+     * Generates a unique temporary file name in the app cache directory.
+     */
+    public static String getTempFileName(String id, Context context) throws IOException {
+        return File.createTempFile(replaceFileNameDangerousCharacters(id), null).getAbsolutePath();
+    }
+
+    /**
      * Returns a file address from a resource, or null if it cannot be opened.
      */
     private static AssetFileAddress loadFallbackResource(final Context context,
@@ -178,7 +185,7 @@ class BinaryDictionaryGetter {
                 context.getApplicationInfo().sourceDir, afd.getStartOffset(), afd.getLength());
     }
 
-    static private class DictPackSettings {
+    private static final class DictPackSettings {
         final SharedPreferences mDictPreferences;
         public DictPackSettings(final Context context) {
             Context dictPackContext = null;
@@ -237,7 +244,7 @@ class BinaryDictionaryGetter {
     /**
      * Utility class for the {@link #getCachedWordLists} method
      */
-    private static class FileAndMatchLevel {
+    private static final class FileAndMatchLevel {
         final File mFile;
         final int mMatchLevel;
         public FileAndMatchLevel(final File file, final int matchLevel) {
@@ -350,7 +357,7 @@ class BinaryDictionaryGetter {
     // of the dictionary would lose whitelist functionality.
     private static boolean hackCanUseDictionaryFile(final Locale locale, final File f) {
         // Only for English - other languages didn't have a whitelist, hence this
-        // ad-hock ## HACK ##
+        // ad-hoc ## HACK ##
         if (!Locale.ENGLISH.getLanguage().equals(locale.getLanguage())) return true;
 
         FileInputStream inStream = null;
diff --git a/java/src/com/android/inputmethod/latin/BoundedTreeSet.java b/java/src/com/android/inputmethod/latin/BoundedTreeSet.java
index cf977617d..7f7ff31c8 100644
--- a/java/src/com/android/inputmethod/latin/BoundedTreeSet.java
+++ b/java/src/com/android/inputmethod/latin/BoundedTreeSet.java
@@ -25,7 +25,7 @@ import java.util.TreeSet;
 /**
  * A TreeSet that is bounded in size and throws everything that's smaller than its limit
  */
-public class BoundedTreeSet extends TreeSet<SuggestedWordInfo> {
+public final class BoundedTreeSet extends TreeSet<SuggestedWordInfo> {
     private final int mCapacity;
     public BoundedTreeSet(final Comparator<SuggestedWordInfo> comparator, final int capacity) {
         super(comparator);
diff --git a/java/src/com/android/inputmethod/latin/Constants.java b/java/src/com/android/inputmethod/latin/Constants.java
index 57e12a64f..ba932e590 100644
--- a/java/src/com/android/inputmethod/latin/Constants.java
+++ b/java/src/com/android/inputmethod/latin/Constants.java
@@ -136,11 +136,81 @@ public final class Constants {
 
     public static final int NOT_A_CODE = -1;
 
-    // See {@link KeyboardActionListener.Adapter#isInvalidCoordinate(int)}.
     public static final int NOT_A_COORDINATE = -1;
     public static final int SUGGESTION_STRIP_COORDINATE = -2;
     public static final int SPELL_CHECKER_COORDINATE = -3;
 
+    public static boolean isValidCoordinate(final int coordinate) {
+        // Detect {@link NOT_A_COORDINATE}, {@link SUGGESTION_STRIP_COORDINATE},
+        // and {@link SPELL_CHECKER_COORDINATE}.
+        return coordinate >= 0;
+    }
+
+    /**
+     * Some common keys code. Must be positive.
+     */
+    public static final int CODE_ENTER = '\n';
+    public static final int CODE_TAB = '\t';
+    public static final int CODE_SPACE = ' ';
+    public static final int CODE_PERIOD = '.';
+    public static final int CODE_DASH = '-';
+    public static final int CODE_SINGLE_QUOTE = '\'';
+    public static final int CODE_DOUBLE_QUOTE = '"';
+    public static final int CODE_QUESTION_MARK = '?';
+    public static final int CODE_EXCLAMATION_MARK = '!';
+    // TODO: Check how this should work for right-to-left languages. It seems to stand
+    // that for rtl languages, a closing parenthesis is a left parenthesis. Is this
+    // managed by the font? Or is it a different char?
+    public static final int CODE_CLOSING_PARENTHESIS = ')';
+    public static final int CODE_CLOSING_SQUARE_BRACKET = ']';
+    public static final int CODE_CLOSING_CURLY_BRACKET = '}';
+    public static final int CODE_CLOSING_ANGLE_BRACKET = '>';
+
+    /**
+     * Special keys code. Must be negative.
+     * These should be aligned with KeyboardCodesSet.ID_TO_NAME[],
+     * KeyboardCodesSet.DEFAULT[] and KeyboardCodesSet.RTL[]
+     */
+    public static final int CODE_SHIFT = -1;
+    public static final int CODE_SWITCH_ALPHA_SYMBOL = -2;
+    public static final int CODE_OUTPUT_TEXT = -3;
+    public static final int CODE_DELETE = -4;
+    public static final int CODE_SETTINGS = -5;
+    public static final int CODE_SHORTCUT = -6;
+    public static final int CODE_ACTION_ENTER = -7;
+    public static final int CODE_ACTION_NEXT = -8;
+    public static final int CODE_ACTION_PREVIOUS = -9;
+    public static final int CODE_LANGUAGE_SWITCH = -10;
+    public static final int CODE_RESEARCH = -11;
+    // Code value representing the code is not specified.
+    public static final int CODE_UNSPECIFIED = -12;
+
+    public static boolean isLetterCode(final int code) {
+        return code >= CODE_SPACE;
+    }
+
+    public static String printableCode(final int code) {
+        switch (code) {
+        case CODE_SHIFT: return "shift";
+        case CODE_SWITCH_ALPHA_SYMBOL: return "symbol";
+        case CODE_OUTPUT_TEXT: return "text";
+        case CODE_DELETE: return "delete";
+        case CODE_SETTINGS: return "settings";
+        case CODE_SHORTCUT: return "shortcut";
+        case CODE_ACTION_ENTER: return "actionEnter";
+        case CODE_ACTION_NEXT: return "actionNext";
+        case CODE_ACTION_PREVIOUS: return "actionPrevious";
+        case CODE_LANGUAGE_SWITCH: return "languageSwitch";
+        case CODE_UNSPECIFIED: return "unspec";
+        case CODE_TAB: return "tab";
+        case CODE_ENTER: return "enter";
+        default:
+            if (code < CODE_SPACE) return String.format("'\\u%02x'", code);
+            if (code < 0x100) return String.format("'%c'", code);
+            return String.format("'\\u%04x'", code);
+        }
+    }
+
     private Constants() {
         // This utility class is not publicly instantiable.
     }
diff --git a/java/src/com/android/inputmethod/latin/ContactsBinaryDictionary.java b/java/src/com/android/inputmethod/latin/ContactsBinaryDictionary.java
index 5edc4314f..d1b32a2f3 100644
--- a/java/src/com/android/inputmethod/latin/ContactsBinaryDictionary.java
+++ b/java/src/com/android/inputmethod/latin/ContactsBinaryDictionary.java
@@ -24,8 +24,6 @@ import android.provider.ContactsContract.Contacts;
 import android.text.TextUtils;
 import android.util.Log;
 
-import com.android.inputmethod.keyboard.Keyboard;
-
 import java.util.Locale;
 
 public class ContactsBinaryDictionary extends ExpandableBinaryDictionary {
@@ -62,7 +60,7 @@ public class ContactsBinaryDictionary extends ExpandableBinaryDictionary {
      */
     private final boolean mUseFirstLastBigrams;
 
-    public ContactsBinaryDictionary(final Context context, Locale locale) {
+    public ContactsBinaryDictionary(final Context context, final Locale locale) {
         super(context, getFilenameWithLocale(NAME, locale.toString()), Dictionary.TYPE_CONTACTS);
         mLocale = locale;
         mUseFirstLastBigrams = useFirstLastBigramsForLocale(locale);
@@ -120,7 +118,7 @@ public class ContactsBinaryDictionary extends ExpandableBinaryDictionary {
         }
     }
 
-    private boolean useFirstLastBigramsForLocale(Locale locale) {
+    private boolean useFirstLastBigramsForLocale(final Locale locale) {
         // TODO: Add firstname/lastname bigram rules for other languages.
         if (locale != null && locale.getLanguage().equals(Locale.ENGLISH.getLanguage())) {
             return true;
@@ -128,7 +126,7 @@ public class ContactsBinaryDictionary extends ExpandableBinaryDictionary {
         return false;
     }
 
-    private void addWords(Cursor cursor) {
+    private void addWords(final Cursor cursor) {
         clearFusionDictionary();
         int count = 0;
         while (!cursor.isAfterLast() && count < MAX_CONTACT_COUNT) {
@@ -160,7 +158,7 @@ public class ContactsBinaryDictionary extends ExpandableBinaryDictionary {
      * Adds the words in a name (e.g., firstname/lastname) to the binary dictionary along with their
      * bigrams depending on locale.
      */
-    private void addName(String name) {
+    private void addName(final String name) {
         int len = StringUtils.codePointCount(name);
         String prevWord = null;
         // TODO: Better tokenization for non-Latin writing systems
@@ -188,12 +186,13 @@ public class ContactsBinaryDictionary extends ExpandableBinaryDictionary {
     /**
      * Returns the index of the last letter in the word, starting from position startIndex.
      */
-    private static int getWordEndPosition(String string, int len, int startIndex) {
+    private static int getWordEndPosition(final String string, final int len,
+            final int startIndex) {
         int end;
         int cp = 0;
         for (end = startIndex + 1; end < len; end += Character.charCount(cp)) {
             cp = string.codePointAt(end);
-            if (!(cp == Keyboard.CODE_DASH || cp == Keyboard.CODE_SINGLE_QUOTE
+            if (!(cp == Constants.CODE_DASH || cp == Constants.CODE_SINGLE_QUOTE
                     || Character.isLetter(cp))) {
                 break;
             }
@@ -249,7 +248,7 @@ public class ContactsBinaryDictionary extends ExpandableBinaryDictionary {
         return false;
     }
 
-    private static boolean isValidName(String name) {
+    private static boolean isValidName(final String name) {
         if (name != null && -1 == name.indexOf('@')) {
             return true;
         }
@@ -259,7 +258,7 @@ public class ContactsBinaryDictionary extends ExpandableBinaryDictionary {
     /**
      * Checks if the words in a name are in the current binary dictionary.
      */
-    private boolean isNameInDictionary(String name) {
+    private boolean isNameInDictionary(final String name) {
         int len = StringUtils.codePointCount(name);
         String prevWord = null;
         for (int i = 0; i < len; i++) {
diff --git a/java/src/com/android/inputmethod/latin/DebugSettings.java b/java/src/com/android/inputmethod/latin/DebugSettings.java
index af7649863..3af3cab2c 100644
--- a/java/src/com/android/inputmethod/latin/DebugSettings.java
+++ b/java/src/com/android/inputmethod/latin/DebugSettings.java
@@ -23,17 +23,20 @@ import android.content.pm.PackageManager.NameNotFoundException;
 import android.os.Bundle;
 import android.os.Process;
 import android.preference.CheckBoxPreference;
+import android.preference.Preference;
 import android.preference.PreferenceFragment;
 import android.util.Log;
 
 import com.android.inputmethod.keyboard.KeyboardSwitcher;
+import com.android.inputmethod.research.ResearchLogger;
 
-public class DebugSettings extends PreferenceFragment
+public final class DebugSettings extends PreferenceFragment
         implements SharedPreferences.OnSharedPreferenceChangeListener {
 
     private static final String TAG = DebugSettings.class.getSimpleName();
     private static final String DEBUG_MODE_KEY = "debug_mode";
     public static final String FORCE_NON_DISTINCT_MULTITOUCH_KEY = "force_non_distinct_multitouch";
+    public static final String PREF_USABILITY_STUDY_MODE = "usability_study_mode";
 
     private boolean mServiceNeedsRestart = false;
     private CheckBoxPreference mDebugMode;
@@ -45,6 +48,14 @@ public class DebugSettings extends PreferenceFragment
         SharedPreferences prefs = getPreferenceManager().getSharedPreferences();
         prefs.registerOnSharedPreferenceChangeListener(this);
 
+        final Preference usabilityStudyPref = findPreference(PREF_USABILITY_STUDY_MODE);
+        if (usabilityStudyPref instanceof CheckBoxPreference) {
+            final CheckBoxPreference checkbox = (CheckBoxPreference)usabilityStudyPref;
+            checkbox.setChecked(prefs.getBoolean(PREF_USABILITY_STUDY_MODE,
+                    ResearchLogger.DEFAULT_USABILITY_STUDY_MODE));
+            checkbox.setSummary(R.string.settings_warning_researcher_mode);
+        }
+
         mServiceNeedsRestart = false;
         mDebugMode = (CheckBoxPreference) findPreference(DEBUG_MODE_KEY);
         updateDebugMode();
diff --git a/java/src/com/android/inputmethod/latin/DebugSettingsActivity.java b/java/src/com/android/inputmethod/latin/DebugSettingsActivity.java
index cde20606a..6ef19ee82 100644
--- a/java/src/com/android/inputmethod/latin/DebugSettingsActivity.java
+++ b/java/src/com/android/inputmethod/latin/DebugSettingsActivity.java
@@ -20,7 +20,7 @@ import android.content.Intent;
 import android.os.Bundle;
 import android.preference.PreferenceActivity;
 
-public class DebugSettingsActivity extends PreferenceActivity {
+public final class DebugSettingsActivity extends PreferenceActivity {
     @Override
     public Intent getIntent() {
         final Intent modIntent = new Intent(super.getIntent());
diff --git a/java/src/com/android/inputmethod/latin/DicTraverseSession.java b/java/src/com/android/inputmethod/latin/DicTraverseSession.java
index 359da72cc..ce1b64660 100644
--- a/java/src/com/android/inputmethod/latin/DicTraverseSession.java
+++ b/java/src/com/android/inputmethod/latin/DicTraverseSession.java
@@ -18,7 +18,7 @@ package com.android.inputmethod.latin;
 
 import java.util.Locale;
 
-public class DicTraverseSession {
+public final class DicTraverseSession {
     static {
         JniUtils.loadNativeLibrary();
     }
diff --git a/java/src/com/android/inputmethod/latin/Dictionary.java b/java/src/com/android/inputmethod/latin/Dictionary.java
index 88d0c09dd..8207bc47f 100644
--- a/java/src/com/android/inputmethod/latin/Dictionary.java
+++ b/java/src/com/android/inputmethod/latin/Dictionary.java
@@ -59,12 +59,12 @@ public abstract class Dictionary {
     // TODO: pass more context than just the previous word, to enable better suggestions (n-gram
     // and more)
     abstract public ArrayList<SuggestedWordInfo> getSuggestions(final WordComposer composer,
-            final CharSequence prevWord, final ProximityInfo proximityInfo);
+            final String prevWord, final ProximityInfo proximityInfo);
 
     // The default implementation of this method ignores sessionId.
     // Subclasses that want to use sessionId need to override this method.
     public ArrayList<SuggestedWordInfo> getSuggestionsWithSessionId(final WordComposer composer,
-            final CharSequence prevWord, final ProximityInfo proximityInfo, int sessionId) {
+            final String prevWord, final ProximityInfo proximityInfo, final int sessionId) {
         return getSuggestions(composer, prevWord, proximityInfo);
     }
 
@@ -73,9 +73,9 @@ public abstract class Dictionary {
      * @param word the word to search for. The search should be case-insensitive.
      * @return true if the word exists, false otherwise
      */
-    abstract public boolean isValidWord(CharSequence word);
+    abstract public boolean isValidWord(final String word);
 
-    public int getFrequency(CharSequence word) {
+    public int getFrequency(final String word) {
         return NOT_A_PROBABILITY;
     }
 
@@ -87,7 +87,7 @@ public abstract class Dictionary {
      * @param typedWord the word to compare with
      * @return true if they are the same, false otherwise.
      */
-    protected boolean same(final char[] word, final int length, final CharSequence typedWord) {
+    protected boolean same(final char[] word, final int length, final String typedWord) {
         if (typedWord.length() != length) {
             return false;
         }
diff --git a/java/src/com/android/inputmethod/latin/DictionaryCollection.java b/java/src/com/android/inputmethod/latin/DictionaryCollection.java
index 4acab6b05..7f78ac8a2 100644
--- a/java/src/com/android/inputmethod/latin/DictionaryCollection.java
+++ b/java/src/com/android/inputmethod/latin/DictionaryCollection.java
@@ -29,7 +29,7 @@ import java.util.concurrent.CopyOnWriteArrayList;
 /**
  * Class for a collection of dictionaries that behave like one dictionary.
  */
-public class DictionaryCollection extends Dictionary {
+public final class DictionaryCollection extends Dictionary {
     private final String TAG = DictionaryCollection.class.getSimpleName();
     protected final CopyOnWriteArrayList<Dictionary> mDictionaries;
 
@@ -56,7 +56,7 @@ public class DictionaryCollection extends Dictionary {
 
     @Override
     public ArrayList<SuggestedWordInfo> getSuggestions(final WordComposer composer,
-            final CharSequence prevWord, final ProximityInfo proximityInfo) {
+            final String prevWord, final ProximityInfo proximityInfo) {
         final CopyOnWriteArrayList<Dictionary> dictionaries = mDictionaries;
         if (dictionaries.isEmpty()) return null;
         // To avoid creating unnecessary objects, we get the list out of the first
@@ -74,14 +74,14 @@ public class DictionaryCollection extends Dictionary {
     }
 
     @Override
-    public boolean isValidWord(CharSequence word) {
+    public boolean isValidWord(final String word) {
         for (int i = mDictionaries.size() - 1; i >= 0; --i)
             if (mDictionaries.get(i).isValidWord(word)) return true;
         return false;
     }
 
     @Override
-    public int getFrequency(CharSequence word) {
+    public int getFrequency(final String word) {
         int maxFreq = -1;
         for (int i = mDictionaries.size() - 1; i >= 0; --i) {
             final int tempFreq = mDictionaries.get(i).getFrequency(word);
diff --git a/java/src/com/android/inputmethod/latin/DictionaryFactory.java b/java/src/com/android/inputmethod/latin/DictionaryFactory.java
index cdd01d0c7..f381973ae 100644
--- a/java/src/com/android/inputmethod/latin/DictionaryFactory.java
+++ b/java/src/com/android/inputmethod/latin/DictionaryFactory.java
@@ -29,7 +29,7 @@ import java.util.Locale;
 /**
  * Factory for dictionary instances.
  */
-public class DictionaryFactory {
+public final class DictionaryFactory {
     private static final String TAG = DictionaryFactory.class.getSimpleName();
     // This class must be located in the same package as LatinIME.java.
     private static final String RESOURCE_PACKAGE_NAME =
diff --git a/java/src/com/android/inputmethod/latin/DictionaryPackInstallBroadcastReceiver.java b/java/src/com/android/inputmethod/latin/DictionaryPackInstallBroadcastReceiver.java
index 9c37d7673..f2f3fbded 100644
--- a/java/src/com/android/inputmethod/latin/DictionaryPackInstallBroadcastReceiver.java
+++ b/java/src/com/android/inputmethod/latin/DictionaryPackInstallBroadcastReceiver.java
@@ -27,7 +27,7 @@ import android.net.Uri;
 /**
  * Takes action to reload the necessary data when a dictionary pack was added/removed.
  */
-public class DictionaryPackInstallBroadcastReceiver extends BroadcastReceiver {
+public final class DictionaryPackInstallBroadcastReceiver extends BroadcastReceiver {
 
     final LatinIME mService;
     /**
diff --git a/java/src/com/android/inputmethod/latin/ExpandableBinaryDictionary.java b/java/src/com/android/inputmethod/latin/ExpandableBinaryDictionary.java
index b93c17f11..159867ade 100644
--- a/java/src/com/android/inputmethod/latin/ExpandableBinaryDictionary.java
+++ b/java/src/com/android/inputmethod/latin/ExpandableBinaryDictionary.java
@@ -198,7 +198,7 @@ abstract public class ExpandableBinaryDictionary extends Dictionary {
 
     @Override
     public ArrayList<SuggestedWordInfo> getSuggestions(final WordComposer composer,
-            final CharSequence prevWord, final ProximityInfo proximityInfo) {
+            final String prevWord, final ProximityInfo proximityInfo) {
         asyncReloadDictionaryIfRequired();
         if (mLocalDictionaryController.tryLock()) {
             try {
@@ -213,12 +213,12 @@ abstract public class ExpandableBinaryDictionary extends Dictionary {
     }
 
     @Override
-    public boolean isValidWord(final CharSequence word) {
+    public boolean isValidWord(final String word) {
         asyncReloadDictionaryIfRequired();
         return isValidWordInner(word);
     }
 
-    protected boolean isValidWordInner(final CharSequence word) {
+    protected boolean isValidWordInner(final String word) {
         if (mLocalDictionaryController.tryLock()) {
             try {
                 return isValidWordLocked(word);
@@ -229,17 +229,17 @@ abstract public class ExpandableBinaryDictionary extends Dictionary {
         return false;
     }
 
-    protected boolean isValidWordLocked(final CharSequence word) {
+    protected boolean isValidWordLocked(final String word) {
         if (mBinaryDictionary == null) return false;
         return mBinaryDictionary.isValidWord(word);
     }
 
-    protected boolean isValidBigram(final CharSequence word1, final CharSequence word2) {
+    protected boolean isValidBigram(final String word1, final String word2) {
         if (mBinaryDictionary == null) return false;
         return mBinaryDictionary.isValidBigram(word1, word2);
     }
 
-    protected boolean isValidBigramInner(final CharSequence word1, final CharSequence word2) {
+    protected boolean isValidBigramInner(final String word1, final String word2) {
         if (mLocalDictionaryController.tryLock()) {
             try {
                 return isValidBigramLocked(word1, word2);
@@ -250,7 +250,7 @@ abstract public class ExpandableBinaryDictionary extends Dictionary {
         return false;
     }
 
-    protected boolean isValidBigramLocked(final CharSequence word1, final CharSequence word2) {
+    protected boolean isValidBigramLocked(final String word1, final String word2) {
         if (mBinaryDictionary == null) return false;
         return mBinaryDictionary.isValidBigram(word1, word2);
     }
diff --git a/java/src/com/android/inputmethod/latin/ExpandableDictionary.java b/java/src/com/android/inputmethod/latin/ExpandableDictionary.java
index 8a38d1e1b..16cc1b35f 100644
--- a/java/src/com/android/inputmethod/latin/ExpandableDictionary.java
+++ b/java/src/com/android/inputmethod/latin/ExpandableDictionary.java
@@ -19,7 +19,6 @@ package com.android.inputmethod.latin;
 import android.content.Context;
 import android.text.TextUtils;
 
-import com.android.inputmethod.keyboard.Keyboard;
 import com.android.inputmethod.keyboard.ProximityInfo;
 import com.android.inputmethod.latin.SuggestedWords.SuggestedWordInfo;
 import com.android.inputmethod.latin.UserHistoryForgettingCurveUtils.ForgettingCurveParams;
@@ -48,7 +47,7 @@ public class ExpandableDictionary extends Dictionary {
     // Use this lock before touching mUpdatingDictionary & mRequiresDownload
     private Object mUpdatingLock = new Object();
 
-    private static class Node {
+    private static final class Node {
         Node() {}
         char mCode;
         int mFrequency;
@@ -60,7 +59,7 @@ public class ExpandableDictionary extends Dictionary {
         LinkedList<NextWord> mNGrams; // Supports ngram
     }
 
-    private static class NodeArray {
+    private static final class NodeArray {
         Node[] mData;
         int mLength = 0;
         private static final int INCREMENT = 2;
@@ -69,7 +68,7 @@ public class ExpandableDictionary extends Dictionary {
             mData = new Node[INCREMENT];
         }
 
-        void add(Node n) {
+        void add(final Node n) {
             if (mLength + 1 > mData.length) {
                 Node[] tempData = new Node[mLength + INCREMENT];
                 if (mLength > 0) {
@@ -88,7 +87,7 @@ public class ExpandableDictionary extends Dictionary {
         public int notifyTypedAgainAndGetFrequency();
     }
 
-    private static class NextStaticWord implements NextWord {
+    private static final class NextStaticWord implements NextWord {
         public final Node mWord;
         private final int mFrequency;
         public NextStaticWord(Node word, int frequency) {
@@ -117,7 +116,7 @@ public class ExpandableDictionary extends Dictionary {
         }
     }
 
-    private static class NextHistoryWord implements NextWord {
+    private static final class NextHistoryWord implements NextWord {
         public final Node mWord;
         public final ForgettingCurveParams mFcp;
 
@@ -172,7 +171,7 @@ public class ExpandableDictionary extends Dictionary {
         }
     }
 
-    public void setRequiresReload(boolean reload) {
+    public void setRequiresReload(final boolean reload) {
         synchronized (mUpdatingLock) {
             mRequiresReload = reload;
         }
@@ -202,8 +201,8 @@ public class ExpandableDictionary extends Dictionary {
         addWordRec(mRoots, word, 0, shortcutTarget, frequency, null);
     }
 
-    private void addWordRec(NodeArray children, final String word, final int depth,
-            final String shortcutTarget, final int frequency, Node parentNode) {
+    private void addWordRec(final NodeArray children, final String word, final int depth,
+            final String shortcutTarget, final int frequency, final Node parentNode) {
         final int wordLength = word.length();
         if (wordLength <= depth) return;
         final char c = word.charAt(depth);
@@ -248,7 +247,7 @@ public class ExpandableDictionary extends Dictionary {
 
     @Override
     public ArrayList<SuggestedWordInfo> getSuggestions(final WordComposer composer,
-            final CharSequence prevWord, final ProximityInfo proximityInfo) {
+            final String prevWord, final ProximityInfo proximityInfo) {
         if (reloadDictionaryIfRequired()) return null;
         if (composer.size() > 1) {
             if (composer.size() >= BinaryDictionary.MAX_WORD_LENGTH) {
@@ -267,8 +266,7 @@ public class ExpandableDictionary extends Dictionary {
 
     // This reloads the dictionary if required, and returns whether it's currently updating its
     // contents or not.
-    // @VisibleForTesting
-    boolean reloadDictionaryIfRequired() {
+    private boolean reloadDictionaryIfRequired() {
         synchronized (mUpdatingLock) {
             // If we need to update, start off a background task
             if (mRequiresReload) startDictionaryLoadingTaskLocked();
@@ -277,7 +275,7 @@ public class ExpandableDictionary extends Dictionary {
     }
 
     protected ArrayList<SuggestedWordInfo> getWordsInner(final WordComposer codes,
-            final CharSequence prevWordForBigrams, final ProximityInfo proximityInfo) {
+            final String prevWordForBigrams, final ProximityInfo proximityInfo) {
         final ArrayList<SuggestedWordInfo> suggestions = CollectionUtils.newArrayList();
         mInputLength = codes.size();
         if (mCodes.length < mInputLength) mCodes = new int[mInputLength][];
@@ -305,7 +303,7 @@ public class ExpandableDictionary extends Dictionary {
     }
 
     @Override
-    public synchronized boolean isValidWord(CharSequence word) {
+    public synchronized boolean isValidWord(final String word) {
         synchronized (mUpdatingLock) {
             // If we need to update, start off a background task
             if (mRequiresReload) startDictionaryLoadingTaskLocked();
@@ -320,7 +318,7 @@ public class ExpandableDictionary extends Dictionary {
         return (node == null) ? false : !node.mShortcutOnly;
     }
 
-    protected boolean removeBigram(String word1, String word2) {
+    protected boolean removeBigram(final String word1, final String word2) {
         // Refer to addOrSetBigram() about word1.toLowerCase()
         final Node firstWord = searchWord(mRoots, word1.toLowerCase(), 0, null);
         final Node secondWord = searchWord(mRoots, word2, 0, null);
@@ -345,13 +343,13 @@ public class ExpandableDictionary extends Dictionary {
     /**
      * Returns the word's frequency or -1 if not found
      */
-    protected int getWordFrequency(CharSequence word) {
+    protected int getWordFrequency(final String word) {
         // Case-sensitive search
         final Node node = searchNode(mRoots, word, 0, word.length());
         return (node == null) ? -1 : node.mFrequency;
     }
 
-    protected NextWord getBigramWord(String word1, String word2) {
+    protected NextWord getBigramWord(final String word1, final String word2) {
         // Refer to addOrSetBigram() about word1.toLowerCase()
         final Node firstWord = searchWord(mRoots, word1.toLowerCase(), 0, null);
         final Node secondWord = searchWord(mRoots, word2, 0, null);
@@ -368,7 +366,8 @@ public class ExpandableDictionary extends Dictionary {
         return null;
     }
 
-    private static int computeSkippedWordFinalFreq(int freq, int snr, int inputLength) {
+    private static int computeSkippedWordFinalFreq(final int freq, final int snr,
+            final int inputLength) {
         // The computation itself makes sense for >= 2, but the == 2 case returns 0
         // anyway so we may as well test against 3 instead and return the constant
         if (inputLength >= 3) {
@@ -431,9 +430,9 @@ public class ExpandableDictionary extends Dictionary {
      * @param suggestions the list in which to add suggestions
      */
     // TODO: Share this routine with the native code for BinaryDictionary
-    protected void getWordsRec(NodeArray roots, final WordComposer codes, final char[] word,
-            final int depth, final boolean completion, int snr, int inputIndex, int skipPos,
-            final ArrayList<SuggestedWordInfo> suggestions) {
+    protected void getWordsRec(final NodeArray roots, final WordComposer codes, final char[] word,
+            final int depth, final boolean completion, final int snr, final int inputIndex,
+            final int skipPos, final ArrayList<SuggestedWordInfo> suggestions) {
         final int count = roots.mLength;
         final int codeSize = mInputLength;
         // Optimization: Prune out words that are too long compared to how much was typed.
@@ -472,8 +471,8 @@ public class ExpandableDictionary extends Dictionary {
                     getWordsRec(children, codes, word, depth + 1, true, snr, inputIndex,
                             skipPos, suggestions);
                 }
-            } else if ((c == Keyboard.CODE_SINGLE_QUOTE
-                    && currentChars[0] != Keyboard.CODE_SINGLE_QUOTE) || depth == skipPos) {
+            } else if ((c == Constants.CODE_SINGLE_QUOTE
+                    && currentChars[0] != Constants.CODE_SINGLE_QUOTE) || depth == skipPos) {
                 // Skip the ' and continue deeper
                 word[depth] = c;
                 if (children != null) {
@@ -524,11 +523,13 @@ public class ExpandableDictionary extends Dictionary {
         }
     }
 
-    public int setBigramAndGetFrequency(String word1, String word2, int frequency) {
+    public int setBigramAndGetFrequency(final String word1, final String word2,
+            final int frequency) {
         return setBigramAndGetFrequency(word1, word2, frequency, null /* unused */);
     }
 
-    public int setBigramAndGetFrequency(String word1, String word2, ForgettingCurveParams fcp) {
+    public int setBigramAndGetFrequency(final String word1, final String word2,
+            final ForgettingCurveParams fcp) {
         return setBigramAndGetFrequency(word1, word2, 0 /* unused */, fcp);
     }
 
@@ -540,8 +541,8 @@ public class ExpandableDictionary extends Dictionary {
      * @param fcp an instance of ForgettingCurveParams to use for decay policy
      * @return returns the final bigram frequency
      */
-    private int setBigramAndGetFrequency(
-            String word1, String word2, int frequency, ForgettingCurveParams fcp) {
+    private int setBigramAndGetFrequency(final String word1, final String word2,
+            final int frequency, final ForgettingCurveParams fcp) {
         // We don't want results to be different according to case of the looked up left hand side
         // word. We do want however to return the correct case for the right hand side.
         // So we want to squash the case of the left hand side, and preserve that of the right
@@ -572,7 +573,8 @@ public class ExpandableDictionary extends Dictionary {
      * Searches for the word and add the word if it does not exist.
      * @return Returns the terminal node of the word we are searching for.
      */
-    private Node searchWord(NodeArray children, String word, int depth, Node parentNode) {
+    private Node searchWord(final NodeArray children, final String word, final int depth,
+            final Node parentNode) {
         final int wordLength = word.length();
         final char c = word.charAt(depth);
         // Does children have the current character?
@@ -602,36 +604,17 @@ public class ExpandableDictionary extends Dictionary {
         return searchWord(childNode.mChildren, word, depth + 1, childNode);
     }
 
-    private void runBigramReverseLookUp(final CharSequence previousWord,
+    private void runBigramReverseLookUp(final String previousWord,
             final ArrayList<SuggestedWordInfo> suggestions) {
         // Search for the lowercase version of the word only, because that's where bigrams
         // store their sons.
-        Node prevWord = searchNode(mRoots, previousWord.toString().toLowerCase(), 0,
+        final Node prevWord = searchNode(mRoots, previousWord.toLowerCase(), 0,
                 previousWord.length());
         if (prevWord != null && prevWord.mNGrams != null) {
             reverseLookUp(prevWord.mNGrams, suggestions);
         }
     }
 
-    /**
-     * Used for testing purposes and in the spell checker
-     * This function will wait for loading from database to be done
-     */
-    void waitForDictionaryLoading() {
-        while (mUpdatingDictionary) {
-            try {
-                Thread.sleep(100);
-            } catch (InterruptedException e) {
-                //
-            }
-        }
-    }
-
-    protected final void blockingReloadDictionaryIfRequired() {
-        reloadDictionaryIfRequired();
-        waitForDictionaryLoading();
-    }
-
     // Local to reverseLookUp, but do not allocate each time.
     private final char[] mLookedUpString = new char[BinaryDictionary.MAX_WORD_LENGTH];
 
@@ -641,7 +624,7 @@ public class ExpandableDictionary extends Dictionary {
      * @param terminalNodes list of terminal nodes we want to add
      * @param suggestions the suggestion collection to add the word to
      */
-    private void reverseLookUp(LinkedList<NextWord> terminalNodes,
+    private void reverseLookUp(final LinkedList<NextWord> terminalNodes,
             final ArrayList<SuggestedWordInfo> suggestions) {
         Node node;
         int freq;
@@ -703,7 +686,7 @@ public class ExpandableDictionary extends Dictionary {
         mRoots = new NodeArray();
     }
 
-    private class LoadDictionaryTask extends Thread {
+    private final class LoadDictionaryTask extends Thread {
         LoadDictionaryTask() {}
         @Override
         public void run() {
@@ -714,7 +697,7 @@ public class ExpandableDictionary extends Dictionary {
         }
     }
 
-    private static char toLowerCase(char c) {
+    private static char toLowerCase(final char c) {
         char baseChar = c;
         if (c < BASE_CHARS.length) {
             baseChar = BASE_CHARS[c];
diff --git a/java/src/com/android/inputmethod/latin/FileTransforms.java b/java/src/com/android/inputmethod/latin/FileTransforms.java
index 80159521c..09cf23a9b 100644
--- a/java/src/com/android/inputmethod/latin/FileTransforms.java
+++ b/java/src/com/android/inputmethod/latin/FileTransforms.java
@@ -21,7 +21,7 @@ import java.io.InputStream;
 import java.io.OutputStream;
 import java.util.zip.GZIPInputStream;
 
-public class FileTransforms {
+public final class FileTransforms {
     public static OutputStream getCryptedStream(OutputStream out) {
         // Crypt the stream.
         return out;
diff --git a/java/src/com/android/inputmethod/latin/InputAttributes.java b/java/src/com/android/inputmethod/latin/InputAttributes.java
index 7bcda9bc4..2f7608a03 100644
--- a/java/src/com/android/inputmethod/latin/InputAttributes.java
+++ b/java/src/com/android/inputmethod/latin/InputAttributes.java
@@ -23,7 +23,7 @@ import android.view.inputmethod.EditorInfo;
 /**
  * Class to hold attributes of the input field.
  */
-public class InputAttributes {
+public final class InputAttributes {
     private final String TAG = InputAttributes.class.getSimpleName();
 
     final public boolean mInputTypeNoAutoCorrect;
diff --git a/java/src/com/android/inputmethod/latin/InputPointers.java b/java/src/com/android/inputmethod/latin/InputPointers.java
index ff2feb51d..7dffd96dd 100644
--- a/java/src/com/android/inputmethod/latin/InputPointers.java
+++ b/java/src/com/android/inputmethod/latin/InputPointers.java
@@ -16,8 +16,10 @@
 
 package com.android.inputmethod.latin;
 
+import com.android.inputmethod.annotations.UsedForTesting;
+
 // TODO: This class is not thread-safe.
-public class InputPointers {
+public final class InputPointers {
     private final int mDefaultCapacity;
     private final ResizableIntArray mXCoordinates;
     private final ResizableIntArray mYCoordinates;
@@ -39,7 +41,8 @@ public class InputPointers {
         mTimes.add(index, time);
     }
 
-    public void addPointer(int x, int y, int pointerId, int time) {
+    @UsedForTesting
+    void addPointer(int x, int y, int pointerId, int time) {
         mXCoordinates.add(x);
         mYCoordinates.add(y);
         mPointerIds.add(pointerId);
@@ -66,7 +69,8 @@ public class InputPointers {
      * @param startPos the starting index of the pointers in {@code src}.
      * @param length the number of pointers to be appended.
      */
-    public void append(InputPointers src, int startPos, int length) {
+    @UsedForTesting
+    void append(InputPointers src, int startPos, int length) {
         if (length == 0) {
             return;
         }
diff --git a/java/src/com/android/inputmethod/latin/InputView.java b/java/src/com/android/inputmethod/latin/InputView.java
index c15f45345..d7595bfbe 100644
--- a/java/src/com/android/inputmethod/latin/InputView.java
+++ b/java/src/com/android/inputmethod/latin/InputView.java
@@ -23,7 +23,7 @@ import android.view.MotionEvent;
 import android.view.View;
 import android.widget.LinearLayout;
 
-public class InputView extends LinearLayout {
+public final class InputView extends LinearLayout {
     private View mSuggestionStripContainer;
     private View mKeyboardView;
     private int mKeyboardTopPadding;
diff --git a/java/src/com/android/inputmethod/latin/LastComposedWord.java b/java/src/com/android/inputmethod/latin/LastComposedWord.java
index dd73a978c..44ef01204 100644
--- a/java/src/com/android/inputmethod/latin/LastComposedWord.java
+++ b/java/src/com/android/inputmethod/latin/LastComposedWord.java
@@ -22,7 +22,7 @@ import android.text.TextUtils;
  * This class encapsulates data about a word previously composed, but that has been
  * committed already. This is used for resuming suggestion, and cancel auto-correction.
  */
-public class LastComposedWord {
+public final class LastComposedWord {
     // COMMIT_TYPE_USER_TYPED_WORD is used when the word committed is the exact typed word, with
     // no hinting from the IME. It happens when some external event happens (rotating the device,
     // for example) or when auto-correction is off by settings or editor attributes.
@@ -44,7 +44,7 @@ public class LastComposedWord {
     public final String mTypedWord;
     public final String mCommittedWord;
     public final String mSeparatorString;
-    public final CharSequence mPrevWord;
+    public final String mPrevWord;
     public final InputPointers mInputPointers = new InputPointers(BinaryDictionary.MAX_WORD_LENGTH);
 
     private boolean mActive;
@@ -56,7 +56,7 @@ public class LastComposedWord {
     // immutable. Do not fiddle with their contents after you passed them to this constructor.
     public LastComposedWord(final int[] primaryKeyCodes, final InputPointers inputPointers,
             final String typedWord, final String committedWord,
-            final String separatorString, final CharSequence prevWord) {
+            final String separatorString, final String prevWord) {
         mPrimaryKeyCodes = primaryKeyCodes;
         if (inputPointers != null) {
             mInputPointers.copy(inputPointers);
diff --git a/java/src/com/android/inputmethod/latin/LatinIME.java b/java/src/com/android/inputmethod/latin/LatinIME.java
index 9252b0980..2af7b1d61 100644
--- a/java/src/com/android/inputmethod/latin/LatinIME.java
+++ b/java/src/com/android/inputmethod/latin/LatinIME.java
@@ -60,6 +60,7 @@ import android.view.inputmethod.InputMethodSubtype;
 
 import com.android.inputmethod.accessibility.AccessibilityUtils;
 import com.android.inputmethod.accessibility.AccessibleKeyboardViewProxy;
+import com.android.inputmethod.annotations.UsedForTesting;
 import com.android.inputmethod.compat.CompatUtils;
 import com.android.inputmethod.compat.InputMethodManagerCompatWrapper;
 import com.android.inputmethod.compat.InputMethodServiceCompatUtils;
@@ -85,7 +86,7 @@ import java.util.Locale;
 /**
  * Input method implementation for Qwerty'ish keyboard.
  */
-public class LatinIME extends InputMethodService implements KeyboardActionListener,
+public final class LatinIME extends InputMethodService implements KeyboardActionListener,
         SuggestionStripView.Listener, TargetApplicationGetter.OnTargetApplicationKnownListener,
         Suggest.SuggestInitializationListener {
     private static final String TAG = LatinIME.class.getSimpleName();
@@ -132,14 +133,14 @@ public class LatinIME extends InputMethodService implements KeyboardActionListen
     private View mKeyPreviewBackingView;
     private View mSuggestionsContainer;
     private SuggestionStripView mSuggestionStripView;
-    /* package for tests */ Suggest mSuggest;
+    @UsedForTesting Suggest mSuggest;
     private CompletionInfo[] mApplicationSpecifiedCompletions;
     private ApplicationInfo mTargetApplicationInfo;
 
     private InputMethodManagerCompatWrapper mImm;
     private Resources mResources;
     private SharedPreferences mPrefs;
-    /* package for tests */ final KeyboardSwitcher mKeyboardSwitcher;
+    @UsedForTesting final KeyboardSwitcher mKeyboardSwitcher;
     private final SubtypeSwitcher mSubtypeSwitcher;
     private boolean mShouldSwitchToLastSubtype = true;
 
@@ -163,8 +164,6 @@ public class LatinIME extends InputMethodService implements KeyboardActionListen
     private int mDeleteCount;
     private long mLastKeyTime;
 
-    private AudioAndHapticFeedbackManager mFeedbackManager;
-
     // Member variables for remembering the current device orientation.
     private int mDisplayOrientation;
 
@@ -173,7 +172,7 @@ public class LatinIME extends InputMethodService implements KeyboardActionListen
             new DictionaryPackInstallBroadcastReceiver(this);
 
     // Keeps track of most recently inserted text (multi-character key) for reverting
-    private CharSequence mEnteredText;
+    private String mEnteredText;
 
     private boolean mIsAutoCorrectionIndicatorOn;
 
@@ -183,7 +182,7 @@ public class LatinIME extends InputMethodService implements KeyboardActionListen
 
     public final UIHandler mHandler = new UIHandler(this);
 
-    public static class UIHandler extends StaticInnerHandlerWrapper<LatinIME> {
+    public static final class UIHandler extends StaticInnerHandlerWrapper<LatinIME> {
         private static final int MSG_UPDATE_SHIFT_STATE = 0;
         private static final int MSG_PENDING_IMS_CALLBACK = 1;
         private static final int MSG_UPDATE_SUGGESTION_STRIP = 2;
@@ -424,7 +423,7 @@ public class LatinIME extends InputMethodService implements KeyboardActionListen
     }
 
     // Has to be package-visible for unit tests
-    /* package for test */
+    @UsedForTesting
     void loadSettings() {
         // Note that the calling sequence of onCreate() and onCurrentInputMethodSubtypeChanged()
         // is not guaranteed. It may even be called at the same time on a different thread.
@@ -438,7 +437,6 @@ public class LatinIME extends InputMethodService implements KeyboardActionListen
             }
         };
         mCurrentSettings = job.runInLocale(mResources, mSubtypeSwitcher.getCurrentSubtypeLocale());
-        mFeedbackManager = new AudioAndHapticFeedbackManager(this, mCurrentSettings);
         resetContactsDictionary(null == mSuggest ? null : mSuggest.getContactsDictionary());
     }
 
@@ -715,11 +713,13 @@ public class LatinIME extends InputMethodService implements KeyboardActionListen
             mSpaceState = SPACE_STATE_NONE;
 
             if (mSuggestionStripView != null) {
-                mSuggestionStripView.clear();
+                // This will set the punctuation suggestions if next word suggestion is off;
+                // otherwise it will clear the suggestion strip.
+                setPunctuationSuggestions();
             }
         }
 
-        mConnection.resetCachesUponCursorMove(mLastSelectionStart);
+        mConnection.resetCachesUponCursorMove(editorInfo.initialSelStart);
 
         if (isDifferentTextField) {
             mainKeyboardView.closing();
@@ -856,16 +856,25 @@ public class LatinIME extends InputMethodService implements KeyboardActionListen
             // TODO: the following is probably better done in resetEntireInputState().
             // it should only happen when the cursor moved, and the very purpose of the
             // test below is to narrow down whether this happened or not. Likewise with
-            // the call to postUpdateShiftState.
+            // the call to updateShiftState.
             // We set this to NONE because after a cursor move, we don't want the space
             // state-related special processing to kick in.
             mSpaceState = SPACE_STATE_NONE;
 
             if ((!mWordComposer.isComposingWord()) || selectionChanged || noComposingSpan) {
+                // If we are composing a word and moving the cursor, we would want to set a
+                // suggestion span for recorrection to work correctly. Unfortunately, that
+                // would involve the keyboard committing some new text, which would move the
+                // cursor back to where it was. Latin IME could then fix the position of the cursor
+                // again, but the asynchronous nature of the calls results in this wreaking havoc
+                // with selection on double tap and the like.
+                // Another option would be to send suggestions each time we set the composing
+                // text, but that is probably too expensive to do, so we decided to leave things
+                // as is.
                 resetEntireInputState(newSelStart);
             }
 
-            mHandler.postUpdateShiftState();
+            mKeyboardSwitcher.updateShiftState();
         }
         mExpectingUpdateSelection = false;
         // TODO: Decide to call restartSuggestionsOnWordBeforeCursorIfAtEndOfWord() or not
@@ -1052,7 +1061,16 @@ public class LatinIME extends InputMethodService implements KeyboardActionListen
         // Reread resource value here, because this method is called by framework anytime as needed.
         final boolean isFullscreenModeAllowed =
                 mCurrentSettings.isFullscreenModeAllowed(getResources());
-        return super.onEvaluateFullscreenMode() && isFullscreenModeAllowed;
+        if (super.onEvaluateFullscreenMode() && isFullscreenModeAllowed) {
+            // TODO: Remove this hack. Actually we should not really assume NO_EXTRACT_UI
+            // implies NO_FULLSCREEN. However, the framework mistakenly does.  i.e. NO_EXTRACT_UI
+            // without NO_FULLSCREEN doesn't work as expected. Because of this we need this
+            // hack for now.  Let's get rid of this once the framework gets fixed.
+            final EditorInfo ei = getCurrentInputEditorInfo();
+            return !(ei != null && ((ei.imeOptions & EditorInfo.IME_FLAG_NO_EXTRACT_UI) != 0));
+        } else {
+            return false;
+        }
     }
 
     @Override
@@ -1085,13 +1103,10 @@ public class LatinIME extends InputMethodService implements KeyboardActionListen
 
     private void commitTyped(final String separatorString) {
         if (!mWordComposer.isComposingWord()) return;
-        final CharSequence typedWord = mWordComposer.getTypedWord();
+        final String typedWord = mWordComposer.getTypedWord();
         if (typedWord.length() > 0) {
-            mConnection.commitText(typedWord, 1);
-            final CharSequence prevWord = addToUserHistoryDictionary(typedWord);
-            mLastComposedWord = mWordComposer.commitWord(
-                    LastComposedWord.COMMIT_TYPE_USER_TYPED_WORD, typedWord.toString(),
-                    separatorString, prevWord);
+            commitChosenWord(typedWord, LastComposedWord.COMMIT_TYPE_USER_TYPED_WORD,
+                    separatorString);
         }
     }
 
@@ -1111,8 +1126,8 @@ public class LatinIME extends InputMethodService implements KeyboardActionListen
 
     // Factor in auto-caps and manual caps and compute the current caps mode.
     private int getActualCapsMode() {
-        final int manual = mKeyboardSwitcher.getManualCapsMode();
-        if (manual != WordComposer.CAPS_MODE_OFF) return manual;
+        final int keyboardShiftMode = mKeyboardSwitcher.getKeyboardShiftMode();
+        if (keyboardShiftMode != WordComposer.CAPS_MODE_AUTO_SHIFTED) return keyboardShiftMode;
         final int auto = getCurrentAutoCapsState();
         if (0 != (auto & TextUtils.CAP_MODE_CHARACTERS)) {
             return WordComposer.CAPS_MODE_AUTO_SHIFT_LOCKED;
@@ -1125,7 +1140,7 @@ public class LatinIME extends InputMethodService implements KeyboardActionListen
         CharSequence lastTwo = mConnection.getTextBeforeCursor(2, 0);
         // It is guaranteed lastTwo.charAt(1) is a swapper - else this method is not called.
         if (lastTwo != null && lastTwo.length() == 2
-                && lastTwo.charAt(0) == Keyboard.CODE_SPACE) {
+                && lastTwo.charAt(0) == Constants.CODE_SPACE) {
             mConnection.deleteSurroundingText(2, 0);
             mConnection.commitText(lastTwo.charAt(1) + " ", 1);
             if (ProductionFlag.IS_EXPERIMENTAL) {
@@ -1141,8 +1156,8 @@ public class LatinIME extends InputMethodService implements KeyboardActionListen
         final CharSequence lastThree = mConnection.getTextBeforeCursor(3, 0);
         if (lastThree != null && lastThree.length() == 3
                 && canBeFollowedByPeriod(lastThree.charAt(0))
-                && lastThree.charAt(1) == Keyboard.CODE_SPACE
-                && lastThree.charAt(2) == Keyboard.CODE_SPACE) {
+                && lastThree.charAt(1) == Constants.CODE_SPACE
+                && lastThree.charAt(2) == Constants.CODE_SPACE) {
             mHandler.cancelDoubleSpacesTimer();
             mConnection.deleteSurroundingText(2, 0);
             mConnection.commitText(". ", 1);
@@ -1156,12 +1171,12 @@ public class LatinIME extends InputMethodService implements KeyboardActionListen
         // TODO: Check again whether there really ain't a better way to check this.
         // TODO: This should probably be language-dependant...
         return Character.isLetterOrDigit(codePoint)
-                || codePoint == Keyboard.CODE_SINGLE_QUOTE
-                || codePoint == Keyboard.CODE_DOUBLE_QUOTE
-                || codePoint == Keyboard.CODE_CLOSING_PARENTHESIS
-                || codePoint == Keyboard.CODE_CLOSING_SQUARE_BRACKET
-                || codePoint == Keyboard.CODE_CLOSING_CURLY_BRACKET
-                || codePoint == Keyboard.CODE_CLOSING_ANGLE_BRACKET;
+                || codePoint == Constants.CODE_SINGLE_QUOTE
+                || codePoint == Constants.CODE_DOUBLE_QUOTE
+                || codePoint == Constants.CODE_CLOSING_PARENTHESIS
+                || codePoint == Constants.CODE_CLOSING_SQUARE_BRACKET
+                || codePoint == Constants.CODE_CLOSING_CURLY_BRACKET
+                || codePoint == Constants.CODE_CLOSING_ANGLE_BRACKET;
     }
 
     // Callback for the {@link SuggestionStripView}, to call when the "add to dictionary" hint is
@@ -1211,22 +1226,25 @@ public class LatinIME extends InputMethodService implements KeyboardActionListen
         mConnection.performEditorAction(actionId);
     }
 
+    // TODO: Revise the language switch key behavior to make it much smarter and more reasonable.
     private void handleLanguageSwitchKey() {
-        final boolean includesOtherImes = mCurrentSettings.mIncludesOtherImesInLanguageSwitchList;
         final IBinder token = getWindow().getWindow().getAttributes().token;
+        if (mCurrentSettings.mIncludesOtherImesInLanguageSwitchList) {
+            mImm.switchToNextInputMethod(token, false /* onlyCurrentIme */);
+            return;
+        }
         if (mShouldSwitchToLastSubtype) {
             final InputMethodSubtype lastSubtype = mImm.getLastInputMethodSubtype();
             final boolean lastSubtypeBelongsToThisIme =
                     ImfUtils.checkIfSubtypeBelongsToThisImeAndEnabled(this, lastSubtype);
-            if ((includesOtherImes || lastSubtypeBelongsToThisIme)
-                    && mImm.switchToLastInputMethod(token)) {
+            if (lastSubtypeBelongsToThisIme && mImm.switchToLastInputMethod(token)) {
                 mShouldSwitchToLastSubtype = false;
             } else {
-                mImm.switchToNextInputMethod(token, !includesOtherImes);
+                mImm.switchToNextInputMethod(token, true /* onlyCurrentIme */);
                 mShouldSwitchToLastSubtype = true;
             }
         } else {
-            mImm.switchToNextInputMethod(token, !includesOtherImes);
+            mImm.switchToNextInputMethod(token, true /* onlyCurrentIme */);
         }
     }
 
@@ -1253,7 +1271,7 @@ public class LatinIME extends InputMethodService implements KeyboardActionListen
 
         // 16 is android.os.Build.VERSION_CODES.JELLY_BEAN but we can't write it because
         // we want to be able to compile against the Ice Cream Sandwich SDK.
-        if (Keyboard.CODE_ENTER == code && mTargetApplicationInfo != null
+        if (Constants.CODE_ENTER == code && mTargetApplicationInfo != null
                 && mTargetApplicationInfo.targetSdkVersion < 16) {
             // Backward compatibility mode. Before Jelly bean, the keyboard would simulate
             // a hardware keyboard event on pressing enter or delete. This is bad for many
@@ -1270,7 +1288,7 @@ public class LatinIME extends InputMethodService implements KeyboardActionListen
     @Override
     public void onCodeInput(final int primaryCode, final int x, final int y) {
         final long when = SystemClock.uptimeMillis();
-        if (primaryCode != Keyboard.CODE_DELETE || when > mLastKeyTime + QUICK_PRESS) {
+        if (primaryCode != Constants.CODE_DELETE || when > mLastKeyTime + QUICK_PRESS) {
             mDeleteCount = 0;
         }
         mLastKeyTime = when;
@@ -1285,13 +1303,13 @@ public class LatinIME extends InputMethodService implements KeyboardActionListen
         if (!mWordComposer.isComposingWord()) mIsAutoCorrectionIndicatorOn = false;
 
         // TODO: Consolidate the double space timer, mLastKeyTime, and the space state.
-        if (primaryCode != Keyboard.CODE_SPACE) {
+        if (primaryCode != Constants.CODE_SPACE) {
             mHandler.cancelDoubleSpacesTimer();
         }
 
         boolean didAutoCorrect = false;
         switch (primaryCode) {
-        case Keyboard.CODE_DELETE:
+        case Constants.CODE_DELETE:
             mSpaceState = SPACE_STATE_NONE;
             handleBackspace(spaceState);
             mDeleteCount++;
@@ -1299,29 +1317,29 @@ public class LatinIME extends InputMethodService implements KeyboardActionListen
             mShouldSwitchToLastSubtype = true;
             LatinImeLogger.logOnDelete(x, y);
             break;
-        case Keyboard.CODE_SHIFT:
-        case Keyboard.CODE_SWITCH_ALPHA_SYMBOL:
+        case Constants.CODE_SHIFT:
+        case Constants.CODE_SWITCH_ALPHA_SYMBOL:
             // Shift and symbol key is handled in onPressKey() and onReleaseKey().
             break;
-        case Keyboard.CODE_SETTINGS:
+        case Constants.CODE_SETTINGS:
             onSettingsKeyPressed();
             break;
-        case Keyboard.CODE_SHORTCUT:
+        case Constants.CODE_SHORTCUT:
             mSubtypeSwitcher.switchToShortcutIME(this);
             break;
-        case Keyboard.CODE_ACTION_ENTER:
+        case Constants.CODE_ACTION_ENTER:
             performEditorAction(getActionId(switcher.getKeyboard()));
             break;
-        case Keyboard.CODE_ACTION_NEXT:
+        case Constants.CODE_ACTION_NEXT:
             performEditorAction(EditorInfo.IME_ACTION_NEXT);
             break;
-        case Keyboard.CODE_ACTION_PREVIOUS:
+        case Constants.CODE_ACTION_PREVIOUS:
             performEditorAction(EditorInfo.IME_ACTION_PREVIOUS);
             break;
-        case Keyboard.CODE_LANGUAGE_SWITCH:
+        case Constants.CODE_LANGUAGE_SWITCH:
             handleLanguageSwitchKey();
             break;
-        case Keyboard.CODE_RESEARCH:
+        case Constants.CODE_RESEARCH:
             if (ProductionFlag.IS_EXPERIMENTAL) {
                 ResearchLogger.getInstance().onResearchKeySelected(this);
             }
@@ -1357,10 +1375,10 @@ public class LatinIME extends InputMethodService implements KeyboardActionListen
         }
         switcher.onCodeInput(primaryCode);
         // Reset after any single keystroke, except shift and symbol-shift
-        if (!didAutoCorrect && primaryCode != Keyboard.CODE_SHIFT
-                && primaryCode != Keyboard.CODE_SWITCH_ALPHA_SYMBOL)
+        if (!didAutoCorrect && primaryCode != Constants.CODE_SHIFT
+                && primaryCode != Constants.CODE_SWITCH_ALPHA_SYMBOL)
             mLastComposedWord.deactivate();
-        if (Keyboard.CODE_DELETE != primaryCode) {
+        if (Constants.CODE_DELETE != primaryCode) {
             mEnteredText = null;
         }
         mConnection.endBatchEdit();
@@ -1371,7 +1389,7 @@ public class LatinIME extends InputMethodService implements KeyboardActionListen
 
     // Called from PointerTracker through the KeyboardActionListener interface
     @Override
-    public void onTextInput(final CharSequence rawText) {
+    public void onTextInput(final String rawText) {
         mConnection.beginBatchEdit();
         if (mWordComposer.isComposingWord()) {
             commitCurrentAutoCorrection(rawText.toString());
@@ -1379,21 +1397,22 @@ public class LatinIME extends InputMethodService implements KeyboardActionListen
             resetComposingState(true /* alsoResetLastComposedWord */);
         }
         mHandler.postUpdateSuggestionStrip();
-        final CharSequence text = specificTldProcessingOnTextInput(rawText);
+        final String text = specificTldProcessingOnTextInput(rawText);
         if (SPACE_STATE_PHANTOM == mSpaceState) {
-            sendKeyCodePoint(Keyboard.CODE_SPACE);
+            sendKeyCodePoint(Constants.CODE_SPACE);
         }
         mConnection.commitText(text, 1);
         mConnection.endBatchEdit();
         // Space state must be updated before calling updateShiftState
         mSpaceState = SPACE_STATE_NONE;
         mKeyboardSwitcher.updateShiftState();
-        mKeyboardSwitcher.onCodeInput(Keyboard.CODE_OUTPUT_TEXT);
+        mKeyboardSwitcher.onCodeInput(Constants.CODE_OUTPUT_TEXT);
         mEnteredText = text;
     }
 
     @Override
     public void onStartBatchInput() {
+        BatchInputUpdater.getInstance().onStartBatchInput();
         mConnection.beginBatchEdit();
         if (mWordComposer.isComposingWord()) {
             if (ProductionFlag.IS_INTERNAL) {
@@ -1417,6 +1436,16 @@ public class LatinIME extends InputMethodService implements KeyboardActionListen
             // The following is necessary for the case where the user typed something but didn't
             // manual pick it and didn't input any separator.
             mSpaceState = SPACE_STATE_PHANTOM;
+        } else {
+            final int codePointBeforeCursor = mConnection.getCodePointBeforeCursor();
+            // TODO: reverse this logic. We should have the means to determine whether a character
+            // should usually be followed by a space, and it should be more readable.
+            if (Constants.NOT_A_CODE != codePointBeforeCursor
+                    && !Character.isWhitespace(codePointBeforeCursor)
+                    && !mCurrentSettings.isPhantomSpacePromotingSymbol(codePointBeforeCursor)
+                    && !mCurrentSettings.isWeakSpaceStripper(codePointBeforeCursor)) {
+                mSpaceState = SPACE_STATE_PHANTOM;
+            }
         }
         mConnection.endBatchEdit();
         mWordComposer.setCapitalizedModeAtStartComposingTime(getActualCapsMode());
@@ -1425,6 +1454,7 @@ public class LatinIME extends InputMethodService implements KeyboardActionListen
     private static final class BatchInputUpdater implements Handler.Callback {
         private final Handler mHandler;
         private LatinIME mLatinIme;
+        private boolean mInBatchInput; // synchornized using "this".
 
         private BatchInputUpdater() {
             final HandlerThread handlerThread = new HandlerThread(
@@ -1448,17 +1478,32 @@ public class LatinIME extends InputMethodService implements KeyboardActionListen
         public boolean handleMessage(final Message msg) {
             switch (msg.what) {
             case MSG_UPDATE_GESTURE_PREVIEW_AND_SUGGESTION_STRIP:
-                final SuggestedWords suggestedWords = getSuggestedWordsGesture(
-                        (InputPointers)msg.obj, mLatinIme);
-                showGesturePreviewAndSuggestionStrip(
-                        suggestedWords, false /* dismissGestureFloatingPreviewText */, mLatinIme);
+                updateBatchInput((InputPointers)msg.obj, mLatinIme);
                 break;
             }
             return true;
         }
 
-        public void updateGesturePreviewAndSuggestionStrip(final InputPointers batchPointers,
+        // Run in the UI thread.
+        public synchronized void onStartBatchInput() {
+            mInBatchInput = true;
+        }
+
+        // Run in the Handler thread.
+        private synchronized void updateBatchInput(final InputPointers batchPointers,
                 final LatinIME latinIme) {
+            if (!mInBatchInput) {
+                // Batch input has ended while the message was being delivered.
+                return;
+            }
+            final SuggestedWords suggestedWords = getSuggestedWordsGestureLocked(
+                    batchPointers, latinIme);
+            latinIme.mHandler.showGesturePreviewAndSuggestionStrip(
+                    suggestedWords, false /* dismissGestureFloatingPreviewText */);
+        }
+
+        // Run in the UI thread.
+        public void onUpdateBatchInput(final InputPointers batchPointers, final LatinIME latinIme) {
             mLatinIme = latinIme;
             if (mHandler.hasMessages(MSG_UPDATE_GESTURE_PREVIEW_AND_SUGGESTION_STRIP)) {
                 return;
@@ -1468,15 +1513,20 @@ public class LatinIME extends InputMethodService implements KeyboardActionListen
                     .sendToTarget();
         }
 
-        public void showGesturePreviewAndSuggestionStrip(final SuggestedWords suggestedWords,
-                final boolean dismissGestureFloatingPreviewText, final LatinIME latinIme) {
+        // Run in the UI thread.
+        public synchronized SuggestedWords onEndBatchInput(final InputPointers batchPointers,
+                final LatinIME latinIme) {
+            mInBatchInput = false;
+            final SuggestedWords suggestedWords = getSuggestedWordsGestureLocked(
+                    batchPointers, latinIme);
             latinIme.mHandler.showGesturePreviewAndSuggestionStrip(
-                    suggestedWords, dismissGestureFloatingPreviewText);
+                    suggestedWords, true /* dismissGestureFloatingPreviewText */);
+            return suggestedWords;
         }
 
         // {@link LatinIME#getSuggestedWords(int)} method calls with same session id have to
         // be synchronized.
-        public synchronized SuggestedWords getSuggestedWordsGesture(
+        private static SuggestedWords getSuggestedWordsGestureLocked(
                 final InputPointers batchPointers, final LatinIME latinIme) {
             latinIme.mWordComposer.setBatchInputPointers(batchPointers);
             return latinIme.getSuggestedWords(Suggest.SESSION_GESTURE);
@@ -1485,8 +1535,8 @@ public class LatinIME extends InputMethodService implements KeyboardActionListen
 
     private void showGesturePreviewAndSuggestionStrip(final SuggestedWords suggestedWords,
             final boolean dismissGestureFloatingPreviewText) {
-        final String batchInputText = (suggestedWords.size() > 0)
-                ? suggestedWords.getWord(0) : null;
+        final String batchInputText = suggestedWords.isEmpty()
+                ? null : suggestedWords.getWord(0);
         final KeyboardView mainKeyboardView = mKeyboardSwitcher.getMainKeyboardView();
         mainKeyboardView.showGestureFloatingPreviewText(batchInputText);
         showSuggestionStrip(suggestedWords, null);
@@ -1497,25 +1547,22 @@ public class LatinIME extends InputMethodService implements KeyboardActionListen
 
     @Override
     public void onUpdateBatchInput(final InputPointers batchPointers) {
-        BatchInputUpdater.getInstance().updateGesturePreviewAndSuggestionStrip(batchPointers, this);
+        BatchInputUpdater.getInstance().onUpdateBatchInput(batchPointers, this);
     }
 
     @Override
     public void onEndBatchInput(final InputPointers batchPointers) {
-        final BatchInputUpdater batchInputUpdater = BatchInputUpdater.getInstance();
-        final SuggestedWords suggestedWords = batchInputUpdater.getSuggestedWordsGesture(
+        final SuggestedWords suggestedWords = BatchInputUpdater.getInstance().onEndBatchInput(
                 batchPointers, this);
-        batchInputUpdater.showGesturePreviewAndSuggestionStrip(
-                suggestedWords, true /* dismissGestureFloatingPreviewText */, this);
-        final String batchInputText = (suggestedWords.size() > 0)
-                ? suggestedWords.getWord(0) : null;
+        final String batchInputText = suggestedWords.isEmpty()
+                ? null : suggestedWords.getWord(0);
         if (TextUtils.isEmpty(batchInputText)) {
             return;
         }
         mWordComposer.setBatchInputWord(batchInputText);
         mConnection.beginBatchEdit();
         if (SPACE_STATE_PHANTOM == mSpaceState) {
-            sendKeyCodePoint(Keyboard.CODE_SPACE);
+            sendKeyCodePoint(Constants.CODE_SPACE);
         }
         mConnection.setComposingText(batchInputText, 1);
         mExpectingUpdateSelection = true;
@@ -1525,8 +1572,8 @@ public class LatinIME extends InputMethodService implements KeyboardActionListen
         mKeyboardSwitcher.updateShiftState();
     }
 
-    private CharSequence specificTldProcessingOnTextInput(final CharSequence text) {
-        if (text.length() <= 1 || text.charAt(0) != Keyboard.CODE_PERIOD
+    private String specificTldProcessingOnTextInput(final String text) {
+        if (text.length() <= 1 || text.charAt(0) != Constants.CODE_PERIOD
                 || !Character.isLetter(text.charAt(1))) {
             // Not a tld: do nothing.
             return text;
@@ -1534,10 +1581,11 @@ public class LatinIME extends InputMethodService implements KeyboardActionListen
         // We have a TLD (or something that looks like this): make sure we don't add
         // a space even if currently in phantom mode.
         mSpaceState = SPACE_STATE_NONE;
+        // TODO: use getCodePointBeforeCursor instead to improve performance and simplify the code
         final CharSequence lastOne = mConnection.getTextBeforeCursor(1, 0);
         if (lastOne != null && lastOne.length() == 1
-                && lastOne.charAt(0) == Keyboard.CODE_PERIOD) {
-            return text.subSequence(1, text.length());
+                && lastOne.charAt(0) == Constants.CODE_PERIOD) {
+            return text.substring(1);
         } else {
             return text;
         }
@@ -1551,7 +1599,9 @@ public class LatinIME extends InputMethodService implements KeyboardActionListen
     }
 
     private void handleBackspace(final int spaceState) {
-        // In many cases, we may have to put the keyboard in auto-shift state again.
+        // In many cases, we may have to put the keyboard in auto-shift state again. However
+        // we want to wait a few milliseconds before doing it to avoid the keyboard flashing
+        // during key repeat.
         mHandler.postUpdateShiftState();
 
         if (mWordComposer.isComposingWord()) {
@@ -1639,7 +1689,7 @@ public class LatinIME extends InputMethodService implements KeyboardActionListen
 
     private boolean maybeStripSpace(final int code,
             final int spaceState, final boolean isFromSuggestionStrip) {
-        if (Keyboard.CODE_ENTER == code && SPACE_STATE_SWAP_PUNCTUATION == spaceState) {
+        if (Constants.CODE_ENTER == code && SPACE_STATE_SWAP_PUNCTUATION == spaceState) {
             mConnection.removeTrailingSpace();
             return false;
         } else if ((SPACE_STATE_WEAK == spaceState
@@ -1668,7 +1718,7 @@ public class LatinIME extends InputMethodService implements KeyboardActionListen
                 // Sanity check
                 throw new RuntimeException("Should not be composing here");
             }
-            sendKeyCodePoint(Keyboard.CODE_SPACE);
+            sendKeyCodePoint(Constants.CODE_SPACE);
         }
 
         // NOTE: isCursorTouchingWord() is a blocking IPC call, so it often takes several
@@ -1682,7 +1732,7 @@ public class LatinIME extends InputMethodService implements KeyboardActionListen
             // the character is a single quote. The idea here is, single quote is not a
             // separator and it should be treated as a normal character, except in the first
             // position where it should not start composing a word.
-            isComposingWord = (Keyboard.CODE_SINGLE_QUOTE != primaryCode);
+            isComposingWord = (Constants.CODE_SINGLE_QUOTE != primaryCode);
             // Here we don't need to reset the last composed word. It will be reset
             // when we commit this one, if we ever do; if on the other hand we backspace
             // it entirely and resume suggestions on the previous word, we'd like to still
@@ -1691,15 +1741,14 @@ public class LatinIME extends InputMethodService implements KeyboardActionListen
         }
         if (isComposingWord) {
             final int keyX, keyY;
-            if (KeyboardActionListener.Adapter.isInvalidCoordinate(x)
-                    || KeyboardActionListener.Adapter.isInvalidCoordinate(y)) {
-                keyX = x;
-                keyY = y;
-            } else {
+            if (Constants.isValidCoordinate(x) && Constants.isValidCoordinate(y)) {
                 final KeyDetector keyDetector =
                         mKeyboardSwitcher.getMainKeyboardView().getKeyDetector();
                 keyX = keyDetector.getTouchX(x);
                 keyY = keyDetector.getTouchY(y);
+            } else {
+                keyX = x;
+                keyY = y;
             }
             mWordComposer.add(primaryCode, keyX, keyY);
             // If it's the first letter, make note of auto-caps state
@@ -1746,11 +1795,11 @@ public class LatinIME extends InputMethodService implements KeyboardActionListen
 
         if (SPACE_STATE_PHANTOM == spaceState &&
                 mCurrentSettings.isPhantomSpacePromotingSymbol(primaryCode)) {
-            sendKeyCodePoint(Keyboard.CODE_SPACE);
+            sendKeyCodePoint(Constants.CODE_SPACE);
         }
         sendKeyCodePoint(primaryCode);
 
-        if (Keyboard.CODE_SPACE == primaryCode) {
+        if (Constants.CODE_SPACE == primaryCode) {
             if (mCurrentSettings.isSuggestionsRequested(mDisplayOrientation)) {
                 if (maybeDoubleSpace()) {
                     mSpaceState = SPACE_STATE_DOUBLE;
@@ -1791,11 +1840,11 @@ public class LatinIME extends InputMethodService implements KeyboardActionListen
             Utils.Stats.onSeparator((char)primaryCode, x, y);
         }
 
-        mHandler.postUpdateShiftState();
+        mKeyboardSwitcher.updateShiftState();
         return didAutoCorrect;
     }
 
-    private CharSequence getTextWithUnderline(final CharSequence text) {
+    private CharSequence getTextWithUnderline(final String text) {
         return mIsAutoCorrectionIndicatorOn
                 ? SuggestionSpanUtils.getTextWithAutoCorrectionIndicatorUnderline(this, text)
                 : text;
@@ -1812,7 +1861,7 @@ public class LatinIME extends InputMethodService implements KeyboardActionListen
 
     // TODO: make this private
     // Outside LatinIME, only used by the test suite.
-    /* package for tests */
+    @UsedForTesting
     boolean isShowingPunctuationList() {
         if (mSuggestionStripView == null) return false;
         return mCurrentSettings.mSuggestPuncList == mSuggestionStripView.getSuggestions();
@@ -1849,6 +1898,10 @@ public class LatinIME extends InputMethodService implements KeyboardActionListen
             mIsAutoCorrectionIndicatorOn = newAutoCorrectionIndicator;
             final CharSequence textWithUnderline =
                     getTextWithUnderline(mWordComposer.getTypedWord());
+            // TODO: when called from an updateSuggestionStrip() call that results from a posted
+            // message, this is called outside any batch edit. Potentially, this may result in some
+            // janky flickering of the screen, although the display speed makes it unlikely in
+            // the practice.
             mConnection.setComposingText(textWithUnderline, 1);
         }
     }
@@ -1877,21 +1930,25 @@ public class LatinIME extends InputMethodService implements KeyboardActionListen
     }
 
     private SuggestedWords getSuggestedWords(final int sessionId) {
+        final Keyboard keyboard = mKeyboardSwitcher.getKeyboard();
+        if (keyboard == null || mSuggest == null) {
+            return SuggestedWords.EMPTY;
+        }
         final String typedWord = mWordComposer.getTypedWord();
         // Get the word on which we should search the bigrams. If we are composing a word, it's
         // whatever is *before* the half-committed word in the buffer, hence 2; if we aren't, we
         // should just skip whitespace if any, so 1.
         // TODO: this is slow (2-way IPC) - we should probably cache this instead.
-        final CharSequence prevWord =
+        final String prevWord =
                 mConnection.getNthPreviousWord(mCurrentSettings.mWordSeparators,
                 mWordComposer.isComposingWord() ? 2 : 1);
         final SuggestedWords suggestedWords = mSuggest.getSuggestedWords(mWordComposer,
-                prevWord, mKeyboardSwitcher.getKeyboard().getProximityInfo(),
-                mCurrentSettings.mCorrectionEnabled, sessionId);
+                prevWord, keyboard.getProximityInfo(), mCurrentSettings.mCorrectionEnabled,
+                sessionId);
         return maybeRetrieveOlderSuggestions(typedWord, suggestedWords);
     }
 
-    private SuggestedWords maybeRetrieveOlderSuggestions(final CharSequence typedWord,
+    private SuggestedWords maybeRetrieveOlderSuggestions(final String typedWord,
             final SuggestedWords suggestedWords) {
         // TODO: consolidate this into getSuggestedWords
         // We update the suggestion strip only when we have some suggestions to show, i.e. when
@@ -1921,21 +1978,16 @@ public class LatinIME extends InputMethodService implements KeyboardActionListen
         }
     }
 
-    private void showSuggestionStrip(final SuggestedWords suggestedWords,
-            final CharSequence typedWord) {
-        if (null == suggestedWords || suggestedWords.size() <= 0) {
+    private void showSuggestionStrip(final SuggestedWords suggestedWords, final String typedWord) {
+        if (suggestedWords.isEmpty()) {
             clearSuggestionStrip();
             return;
         }
-        final CharSequence autoCorrection;
-        if (suggestedWords.size() > 0) {
-            if (suggestedWords.mWillAutoCorrect) {
-                autoCorrection = suggestedWords.getWord(1);
-            } else {
-                autoCorrection = typedWord;
-            }
+        final String autoCorrection;
+        if (suggestedWords.mWillAutoCorrect) {
+            autoCorrection = suggestedWords.getWord(1);
         } else {
-            autoCorrection = null;
+            autoCorrection = typedWord;
         }
         mWordComposer.setAutoCorrection(autoCorrection);
         final boolean isAutoCorrection = suggestedWords.willAutoCorrect();
@@ -1949,9 +2001,9 @@ public class LatinIME extends InputMethodService implements KeyboardActionListen
         if (mHandler.hasPendingUpdateSuggestions()) {
             updateSuggestionStrip();
         }
-        final CharSequence typedAutoCorrection = mWordComposer.getAutoCorrectionOrNull();
+        final String typedAutoCorrection = mWordComposer.getAutoCorrectionOrNull();
         final String typedWord = mWordComposer.getTypedWord();
-        final CharSequence autoCorrection = (typedAutoCorrection != null)
+        final String autoCorrection = (typedAutoCorrection != null)
                 ? typedAutoCorrection : typedWord;
         if (autoCorrection != null) {
             if (TextUtils.isEmpty(typedWord)) {
@@ -1982,7 +2034,7 @@ public class LatinIME extends InputMethodService implements KeyboardActionListen
     // Called from {@link SuggestionStripView} through the {@link SuggestionStripView#Listener}
     // interface
     @Override
-    public void pickSuggestionManually(final int index, final CharSequence suggestion) {
+    public void pickSuggestionManually(final int index, final String suggestion) {
         final SuggestedWords suggestedWords = mSuggestionStripView.getSuggestions();
         // If this is a punctuation picked from the suggestion strip, pass it to onCodeInput
         if (suggestion.length() == 1 && isShowingPunctuationList()) {
@@ -2007,7 +2059,7 @@ public class LatinIME extends InputMethodService implements KeyboardActionListen
             int firstChar = Character.codePointAt(suggestion, 0);
             if ((!mCurrentSettings.isWeakSpaceStripper(firstChar))
                     && (!mCurrentSettings.isWeakSpaceSwapper(firstChar))) {
-                sendKeyCodePoint(Keyboard.CODE_SPACE);
+                sendKeyCodePoint(Constants.CODE_SPACE);
             }
         }
 
@@ -2052,7 +2104,7 @@ public class LatinIME extends InputMethodService implements KeyboardActionListen
                 && !AutoCorrection.isValidWord(mSuggest.getUnigramDictionaries(), suggestion, true);
 
         if (ProductionFlag.IS_INTERNAL) {
-            Stats.onSeparator((char)Keyboard.CODE_SPACE,
+            Stats.onSeparator((char)Constants.CODE_SPACE,
                     Constants.NOT_A_COORDINATE, Constants.NOT_A_COORDINATE);
         }
         if (showingAddToDictionaryHint && mIsUserDictionaryAvailable) {
@@ -2067,13 +2119,13 @@ public class LatinIME extends InputMethodService implements KeyboardActionListen
     /**
      * Commits the chosen word to the text field and saves it for later retrieval.
      */
-    private void commitChosenWord(final CharSequence chosenWord, final int commitType,
+    private void commitChosenWord(final String chosenWord, final int commitType,
             final String separatorString) {
         final SuggestedWords suggestedWords = mSuggestionStripView.getSuggestions();
         mConnection.commitText(SuggestionSpanUtils.getTextWithSuggestionSpan(
                 this, chosenWord, suggestedWords, mIsMainDictionaryAvailable), 1);
         // Add the word to the user history dictionary
-        final CharSequence prevWord = addToUserHistoryDictionary(chosenWord);
+        final String prevWord = addToUserHistoryDictionary(chosenWord);
         // TODO: figure out here if this is an auto-correct or if the best word is actually
         // what user typed. Note: currently this is done much later in
         // LastComposedWord#didCommitTypedWord by string equality of the remembered
@@ -2092,7 +2144,7 @@ public class LatinIME extends InputMethodService implements KeyboardActionListen
         setSuggestionStripShown(isSuggestionsStripVisible());
     }
 
-    private CharSequence addToUserHistoryDictionary(final CharSequence suggestion) {
+    private String addToUserHistoryDictionary(final String suggestion) {
         if (TextUtils.isEmpty(suggestion)) return null;
         if (mSuggest == null) return null;
 
@@ -2107,19 +2159,18 @@ public class LatinIME extends InputMethodService implements KeyboardActionListen
                     = mConnection.getNthPreviousWord(mCurrentSettings.mWordSeparators, 2);
             final String secondWord;
             if (mWordComposer.wasAutoCapitalized() && !mWordComposer.isMostlyCaps()) {
-                secondWord = suggestion.toString().toLowerCase(
-                        mSubtypeSwitcher.getCurrentSubtypeLocale());
+                secondWord = suggestion.toLowerCase(mSubtypeSwitcher.getCurrentSubtypeLocale());
             } else {
-                secondWord = suggestion.toString();
+                secondWord = suggestion;
             }
             // We demote unrecognized words (frequency < 0, below) by specifying them as "invalid".
             // We don't add words with 0-frequency (assuming they would be profanity etc.).
             final int maxFreq = AutoCorrection.getMaxFrequency(
                     mSuggest.getUnigramDictionaries(), suggestion);
             if (maxFreq == 0) return null;
-            userHistoryDictionary.addToUserHistory(null == prevWord ? null : prevWord.toString(),
-                    secondWord, maxFreq > 0);
-            return prevWord;
+            final String prevWordString = (null == prevWord) ? null : prevWord.toString();
+            userHistoryDictionary.addToUserHistory(prevWordString, secondWord, maxFreq > 0);
+            return prevWordString;
         }
         return null;
     }
@@ -2144,9 +2195,9 @@ public class LatinIME extends InputMethodService implements KeyboardActionListen
     }
 
     private void revertCommit() {
-        final CharSequence previousWord = mLastComposedWord.mPrevWord;
+        final String previousWord = mLastComposedWord.mPrevWord;
         final String originallyTypedWord = mLastComposedWord.mTypedWord;
-        final CharSequence committedWord = mLastComposedWord.mCommittedWord;
+        final String committedWord = mLastComposedWord.mCommittedWord;
         final int cancelLength = committedWord.length();
         final int separatorLength = LastComposedWord.getSeparatorLength(
                 mLastComposedWord.mSeparatorString);
@@ -2156,9 +2207,9 @@ public class LatinIME extends InputMethodService implements KeyboardActionListen
             if (mWordComposer.isComposingWord()) {
                 throw new RuntimeException("revertCommit, but we are composing a word");
             }
-            final String wordBeforeCursor =
+            final CharSequence wordBeforeCursor =
                     mConnection.getTextBeforeCursor(deleteLength, 0)
-                            .subSequence(0, cancelLength).toString();
+                            .subSequence(0, cancelLength);
             if (!TextUtils.equals(committedWord, wordBeforeCursor)) {
                 throw new RuntimeException("revertCommit check failed: we thought we were "
                         + "reverting \"" + committedWord
@@ -2192,7 +2243,7 @@ public class LatinIME extends InputMethodService implements KeyboardActionListen
 
     // TODO: Make this private
     // Outside LatinIME, only used by the {@link InputTestsBase} test suite.
-    /* package for test */
+    @UsedForTesting
     void loadKeyboard() {
         // When the device locale is changed in SetupWizard etc., this method may get called via
         // onConfigurationChanged before SoftInputWindow is shown.
@@ -2208,13 +2259,6 @@ public class LatinIME extends InputMethodService implements KeyboardActionListen
         mHandler.postUpdateSuggestionStrip();
     }
 
-    // TODO: Remove this method from {@link LatinIME} and move {@link FeedbackManager} to
-    // {@link KeyboardSwitcher}. Called from KeyboardSwitcher
-    public void hapticAndAudioFeedback(final int primaryCode) {
-        mFeedbackManager.hapticAndAudioFeedback(
-                primaryCode, mKeyboardSwitcher.getMainKeyboardView());
-    }
-
     // Callback called by PointerTracker through the KeyboardActionListener. This is called when a
     // key is depressed; release matching call is onReleaseKey below.
     @Override
@@ -2231,19 +2275,20 @@ public class LatinIME extends InputMethodService implements KeyboardActionListen
         // If accessibility is on, ensure the user receives keyboard state updates.
         if (AccessibilityUtils.getInstance().isTouchExplorationEnabled()) {
             switch (primaryCode) {
-            case Keyboard.CODE_SHIFT:
+            case Constants.CODE_SHIFT:
                 AccessibleKeyboardViewProxy.getInstance().notifyShiftState();
                 break;
-            case Keyboard.CODE_SWITCH_ALPHA_SYMBOL:
+            case Constants.CODE_SWITCH_ALPHA_SYMBOL:
                 AccessibleKeyboardViewProxy.getInstance().notifySymbolsState();
                 break;
             }
         }
 
-        if (Keyboard.CODE_DELETE == primaryCode) {
+        if (Constants.CODE_DELETE == primaryCode) {
             // This is a stopgap solution to avoid leaving a high surrogate alone in a text view.
             // In the future, we need to deprecate deteleSurroundingText() and have a surrogate
             // pair-friendly way of deleting characters in InputConnection.
+            // TODO: use getCodePointBeforeCursor instead to improve performance
             final CharSequence lastChar = mConnection.getTextBeforeCursor(1, 0);
             if (!TextUtils.isEmpty(lastChar) && Character.isHighSurrogate(lastChar.charAt(0))) {
                 mConnection.deleteSurroundingText(1, 0);
@@ -2259,7 +2304,7 @@ public class LatinIME extends InputMethodService implements KeyboardActionListen
             if (action.equals(ConnectivityManager.CONNECTIVITY_ACTION)) {
                 mSubtypeSwitcher.onNetworkStateChanged(intent);
             } else if (action.equals(AudioManager.RINGER_MODE_CHANGED_ACTION)) {
-                mFeedbackManager.onRingerModeChanged();
+                mKeyboardSwitcher.onRingerModeChanged();
             }
         }
     };
diff --git a/java/src/com/android/inputmethod/latin/LatinImeLogger.java b/java/src/com/android/inputmethod/latin/LatinImeLogger.java
index 9eab19c49..394a9c7aa 100644
--- a/java/src/com/android/inputmethod/latin/LatinImeLogger.java
+++ b/java/src/com/android/inputmethod/latin/LatinImeLogger.java
@@ -21,7 +21,7 @@ import android.view.inputmethod.EditorInfo;
 
 import com.android.inputmethod.keyboard.Keyboard;
 
-public class LatinImeLogger implements SharedPreferences.OnSharedPreferenceChangeListener {
+public final class LatinImeLogger implements SharedPreferences.OnSharedPreferenceChangeListener {
 
     public static boolean sDBG = false;
     public static boolean sVISUALDEBUG = false;
diff --git a/java/src/com/android/inputmethod/latin/ResizableIntArray.java b/java/src/com/android/inputmethod/latin/ResizableIntArray.java
index c660f92c4..9a46f160b 100644
--- a/java/src/com/android/inputmethod/latin/ResizableIntArray.java
+++ b/java/src/com/android/inputmethod/latin/ResizableIntArray.java
@@ -19,7 +19,7 @@ package com.android.inputmethod.latin;
 import java.util.Arrays;
 
 // TODO: This class is not thread-safe.
-public class ResizableIntArray {
+public final class ResizableIntArray {
     private int[] mArray;
     private int mLength;
 
diff --git a/java/src/com/android/inputmethod/latin/RichInputConnection.java b/java/src/com/android/inputmethod/latin/RichInputConnection.java
index 28c0c0f16..53aabd9e8 100644
--- a/java/src/com/android/inputmethod/latin/RichInputConnection.java
+++ b/java/src/com/android/inputmethod/latin/RichInputConnection.java
@@ -26,7 +26,6 @@ import android.view.inputmethod.ExtractedText;
 import android.view.inputmethod.ExtractedTextRequest;
 import android.view.inputmethod.InputConnection;
 
-import com.android.inputmethod.keyboard.Keyboard;
 import com.android.inputmethod.latin.define.ProductionFlag;
 import com.android.inputmethod.research.ResearchLogger;
 
@@ -41,10 +40,11 @@ import java.util.regex.Pattern;
  * all the time to find out what text is in the buffer, when we need it to determine caps mode
  * for example.
  */
-public class RichInputConnection {
+public final class RichInputConnection {
     private static final String TAG = RichInputConnection.class.getSimpleName();
     private static final boolean DBG = false;
     private static final boolean DEBUG_PREVIOUS_TEXT = false;
+    private static final boolean DEBUG_BATCH_NESTING = false;
     // Provision for a long word pair and a separator
     private static final int LOOKBACK_CHARACTER_NUM = BinaryDictionary.MAX_WORD_LENGTH * 2 + 1;
     private static final Pattern spaceRegex = Pattern.compile("\\s+");
@@ -128,7 +128,7 @@ public class RichInputConnection {
                 Log.e(TAG, "Nest level too deep : " + mNestLevel);
             }
         }
-        checkBatchEdit();
+        if (DEBUG_BATCH_NESTING) checkBatchEdit();
         if (DEBUG_PREVIOUS_TEXT) checkConsistencyForDebug();
     }
 
@@ -163,7 +163,11 @@ public class RichInputConnection {
     }
 
     public void finishComposingText() {
+<<<<<<< HEAD
         checkBatchEdit();
+=======
+        if (DEBUG_BATCH_NESTING) checkBatchEdit();
+>>>>>>> goog/master
         if (DEBUG_PREVIOUS_TEXT) checkConsistencyForDebug();
         mCommittedTextBeforeComposingText.append(mComposingText);
         mCurrentCursorPosition += mComposingText.length();
@@ -177,7 +181,11 @@ public class RichInputConnection {
     }
 
     public void commitText(final CharSequence text, final int i) {
+<<<<<<< HEAD
         checkBatchEdit();
+=======
+        if (DEBUG_BATCH_NESTING) checkBatchEdit();
+>>>>>>> goog/master
         if (DEBUG_PREVIOUS_TEXT) checkConsistencyForDebug();
         mCommittedTextBeforeComposingText.append(text);
         mCurrentCursorPosition += text.length() - mComposingText.length();
@@ -234,7 +242,14 @@ public class RichInputConnection {
                 hasSpaceBefore);
     }
 
+    public int getCodePointBeforeCursor() {
+        if (mCommittedTextBeforeComposingText.length() < 1) return Constants.NOT_A_CODE;
+        return Character.codePointBefore(mCommittedTextBeforeComposingText,
+                mCommittedTextBeforeComposingText.length());
+    }
+
     public CharSequence getTextBeforeCursor(final int i, final int j) {
+        // TODO: use mCommittedTextBeforeComposingText if possible to improve performance
         mIC = mParent.getCurrentInputConnection();
         if (null != mIC) return mIC.getTextBeforeCursor(i, j);
         return null;
@@ -247,7 +262,11 @@ public class RichInputConnection {
     }
 
     public void deleteSurroundingText(final int i, final int j) {
+<<<<<<< HEAD
         checkBatchEdit();
+=======
+        if (DEBUG_BATCH_NESTING) checkBatchEdit();
+>>>>>>> goog/master
         final int remainingChars = mComposingText.length() - i;
         if (remainingChars >= 0) {
             mComposingText.setLength(remainingChars);
@@ -283,7 +302,11 @@ public class RichInputConnection {
     }
 
     public void sendKeyEvent(final KeyEvent keyEvent) {
+<<<<<<< HEAD
         checkBatchEdit();
+=======
+        if (DEBUG_BATCH_NESTING) checkBatchEdit();
+>>>>>>> goog/master
         if (keyEvent.getAction() == KeyEvent.ACTION_DOWN) {
             if (DEBUG_PREVIOUS_TEXT) checkConsistencyForDebug();
             // This method is only called for enter or backspace when speaking to old
@@ -331,7 +354,11 @@ public class RichInputConnection {
     }
 
     public void setComposingText(final CharSequence text, final int i) {
+<<<<<<< HEAD
         checkBatchEdit();
+=======
+        if (DEBUG_BATCH_NESTING) checkBatchEdit();
+>>>>>>> goog/master
         if (DEBUG_PREVIOUS_TEXT) checkConsistencyForDebug();
         mCurrentCursorPosition += text.length() - mComposingText.length();
         mComposingText.setLength(0);
@@ -347,7 +374,11 @@ public class RichInputConnection {
     }
 
     public void setSelection(final int from, final int to) {
+<<<<<<< HEAD
         checkBatchEdit();
+=======
+        if (DEBUG_BATCH_NESTING) checkBatchEdit();
+>>>>>>> goog/master
         if (DEBUG_PREVIOUS_TEXT) checkConsistencyForDebug();
         if (null != mIC) {
             mIC.setSelection(from, to);
@@ -361,7 +392,11 @@ public class RichInputConnection {
     }
 
     public void commitCorrection(final CorrectionInfo correctionInfo) {
+<<<<<<< HEAD
         checkBatchEdit();
+=======
+        if (DEBUG_BATCH_NESTING) checkBatchEdit();
+>>>>>>> goog/master
         if (DEBUG_PREVIOUS_TEXT) checkConsistencyForDebug();
         // This has no effect on the text field and does not change its content. It only makes
         // TextView flash the text for a second based on indices contained in the argument.
@@ -375,7 +410,11 @@ public class RichInputConnection {
     }
 
     public void commitCompletion(final CompletionInfo completionInfo) {
+<<<<<<< HEAD
         checkBatchEdit();
+=======
+        if (DEBUG_BATCH_NESTING) checkBatchEdit();
+>>>>>>> goog/master
         if (DEBUG_PREVIOUS_TEXT) checkConsistencyForDebug();
         final CharSequence text = completionInfo.getText();
         mCommittedTextBeforeComposingText.append(text);
@@ -390,7 +429,7 @@ public class RichInputConnection {
         if (DEBUG_PREVIOUS_TEXT) checkConsistencyForDebug();
     }
 
-    public CharSequence getNthPreviousWord(final String sentenceSeperators, final int n) {
+    public String getNthPreviousWord(final String sentenceSeperators, final int n) {
         mIC = mParent.getCurrentInputConnection();
         if (null == mIC) return null;
         final CharSequence prev = mIC.getTextBeforeCursor(LOOKBACK_CHARACTER_NUM, 0);
@@ -415,7 +454,7 @@ public class RichInputConnection {
     /**
      * Represents a range of text, relative to the current cursor position.
      */
-    public static class Range {
+    public static final class Range {
         /** Characters before selection start */
         public final int mCharsBefore;
 
@@ -458,19 +497,22 @@ public class RichInputConnection {
     // (n = 2) "abc|" -> null
     // (n = 2) "abc |" -> null
     // (n = 2) "abc. def|" -> null
-    public static CharSequence getNthPreviousWord(final CharSequence prev,
+    public static String getNthPreviousWord(final CharSequence prev,
             final String sentenceSeperators, final int n) {
         if (prev == null) return null;
-        String[] w = spaceRegex.split(prev);
+        final String[] w = spaceRegex.split(prev);
 
         // If we can't find n words, or we found an empty word, return null.
-        if (w.length < n || w[w.length - n].length() <= 0) return null;
+        if (w.length < n) return null;
+        final String nthPrevWord = w[w.length - n];
+        final int length = nthPrevWord.length();
+        if (length <= 0) return null;
 
         // If ends in a separator, return null
-        char lastChar = w[w.length - n].charAt(w[w.length - n].length() - 1);
+        final char lastChar = nthPrevWord.charAt(length - 1);
         if (sentenceSeperators.contains(String.valueOf(lastChar))) return null;
 
-        return w[w.length - n];
+        return nthPrevWord;
     }
 
     /**
@@ -503,19 +545,20 @@ public class RichInputConnection {
      *   be included in the returned range
      * @return a range containing the text surrounding the cursor
      */
-    public Range getWordRangeAtCursor(String sep, int additionalPrecedingWordsCount) {
+    public Range getWordRangeAtCursor(final String sep, final int additionalPrecedingWordsCount) {
         mIC = mParent.getCurrentInputConnection();
         if (mIC == null || sep == null) {
             return null;
         }
-        CharSequence before = mIC.getTextBeforeCursor(1000, 0);
-        CharSequence after = mIC.getTextAfterCursor(1000, 0);
+        final CharSequence before = mIC.getTextBeforeCursor(1000, 0);
+        final CharSequence after = mIC.getTextAfterCursor(1000, 0);
         if (before == null || after == null) {
             return null;
         }
 
         // Going backward, alternate skipping non-separators and separators until enough words
         // have been read.
+        int count = additionalPrecedingWordsCount;
         int start = before.length();
         boolean isStoppingAtWhitespace = true;  // toggles to indicate what to stop at
         while (true) { // see comments below for why this is guaranteed to halt
@@ -532,7 +575,7 @@ public class RichInputConnection {
             // isStoppingAtWhitespace is true every other time through the loop,
             // so additionalPrecedingWordsCount is guaranteed to become < 0, which
             // guarantees outer loop termination
-            if (isStoppingAtWhitespace && (--additionalPrecedingWordsCount < 0)) {
+            if (isStoppingAtWhitespace && (--count < 0)) {
                 break;  // outer loop
             }
             isStoppingAtWhitespace = !isStoppingAtWhitespace;
@@ -550,7 +593,7 @@ public class RichInputConnection {
             }
         }
 
-        int cursor = getCursorPosition();
+        final int cursor = getCursorPosition();
         if (start >= 0 && cursor + end <= after.length() + before.length()) {
             String word = before.toString().substring(start, before.length())
                     + after.toString().substring(0, end);
@@ -561,8 +604,8 @@ public class RichInputConnection {
     }
 
     public boolean isCursorTouchingWord(final SettingsValues settingsValues) {
-        CharSequence before = getTextBeforeCursor(1, 0);
-        CharSequence after = getTextAfterCursor(1, 0);
+        final CharSequence before = getTextBeforeCursor(1, 0);
+        final CharSequence after = getTextAfterCursor(1, 0);
         if (!TextUtils.isEmpty(before) && !settingsValues.isWordSeparator(before.charAt(0))
                 && !settingsValues.isSymbolExcludedFromWordSeparators(before.charAt(0))) {
             return true;
@@ -575,10 +618,10 @@ public class RichInputConnection {
     }
 
     public void removeTrailingSpace() {
-        checkBatchEdit();
+        if (DEBUG_BATCH_NESTING) checkBatchEdit();
         final CharSequence lastOne = getTextBeforeCursor(1, 0);
         if (lastOne != null && lastOne.length() == 1
-                && lastOne.charAt(0) == Keyboard.CODE_SPACE) {
+                && lastOne.charAt(0) == Constants.CODE_SPACE) {
             deleteSurroundingText(1, 0);
         }
     }
@@ -604,7 +647,7 @@ public class RichInputConnection {
         CharSequence word = getWordAtCursor(settings.mWordSeparators);
         // We don't suggest on leading single quotes, so we have to remove them from the word if
         // it starts with single quotes.
-        while (!TextUtils.isEmpty(word) && Keyboard.CODE_SINGLE_QUOTE == word.charAt(0)) {
+        while (!TextUtils.isEmpty(word) && Constants.CODE_SINGLE_QUOTE == word.charAt(0)) {
             word = word.subSequence(1, word.length());
         }
         if (TextUtils.isEmpty(word)) return null;
@@ -631,7 +674,7 @@ public class RichInputConnection {
     }
 
     public boolean revertDoubleSpace() {
-        checkBatchEdit();
+        if (DEBUG_BATCH_NESTING) checkBatchEdit();
         // Here we test whether we indeed have a period and a space before us. This should not
         // be needed, but it's there just in case something went wrong.
         final CharSequence textBeforeCursor = getTextBeforeCursor(2, 0);
@@ -649,14 +692,14 @@ public class RichInputConnection {
     }
 
     public boolean revertSwapPunctuation() {
-        checkBatchEdit();
+        if (DEBUG_BATCH_NESTING) checkBatchEdit();
         // Here we test whether we indeed have a space and something else before us. This should not
         // be needed, but it's there just in case something went wrong.
         final CharSequence textBeforeCursor = getTextBeforeCursor(2, 0);
         // NOTE: This does not work with surrogate pairs. Hopefully when the keyboard is able to
         // enter surrogate pairs this code will have been removed.
         if (TextUtils.isEmpty(textBeforeCursor)
-                || (Keyboard.CODE_SPACE != textBeforeCursor.charAt(1))) {
+                || (Constants.CODE_SPACE != textBeforeCursor.charAt(1))) {
             // We may only come here if the application is changing the text while we are typing.
             // This is quite a broken case, but not logically impossible, so we shouldn't crash,
             // but some debugging log may be in order.
diff --git a/java/src/com/android/inputmethod/latin/Settings.java b/java/src/com/android/inputmethod/latin/Settings.java
index 9479a88a7..238724610 100644
--- a/java/src/com/android/inputmethod/latin/Settings.java
+++ b/java/src/com/android/inputmethod/latin/Settings.java
@@ -39,12 +39,10 @@ import android.widget.SeekBar.OnSeekBarChangeListener;
 import android.widget.TextView;
 
 import com.android.inputmethod.latin.define.ProductionFlag;
-import com.android.inputmethod.research.ResearchLogger;
 import com.android.inputmethodcommon.InputMethodSettingsFragment;
 
 public final class Settings extends InputMethodSettingsFragment
         implements SharedPreferences.OnSharedPreferenceChangeListener {
-    public static final boolean ENABLE_INTERNAL_SETTINGS = ProductionFlag.IS_INTERNAL;
 
     // In the same order as xml/prefs.xml
     public static final String PREF_GENERAL_SETTINGS = "general_settings";
@@ -58,7 +56,6 @@ public final class Settings extends InputMethodSettingsFragment
     public static final String PREF_AUTO_CORRECTION_THRESHOLD = "auto_correction_threshold";
     public static final String PREF_SHOW_SUGGESTIONS_SETTING = "show_suggestions_setting";
     public static final String PREF_MISC_SETTINGS = "misc_settings";
-    public static final String PREF_USABILITY_STUDY_MODE = "usability_study_mode";
     public static final String PREF_LAST_USER_DICTIONARY_WRITE_TIME =
             "last_user_dictionary_write_time";
     public static final String PREF_ADVANCED_SETTINGS = "pref_advanced_settings";
@@ -77,8 +74,8 @@ public final class Settings extends InputMethodSettingsFragment
     public static final String PREF_KEYPRESS_SOUND_VOLUME =
             "pref_keypress_sound_volume";
     public static final String PREF_GESTURE_PREVIEW_TRAIL = "pref_gesture_preview_trail";
-    public static final String PREF_SHOW_GESTURE_FLOATING_PREVIEW_TEXT =
-            "pref_show_gesture_floating_preview_text";
+    public static final String PREF_GESTURE_FLOATING_PREVIEW_TEXT =
+            "pref_gesture_floating_preview_text";
 
     public static final String PREF_INPUT_LANGUAGE = "input_language";
     public static final String PREF_SELECTED_LANGUAGES = "selected_languages";
@@ -133,14 +130,6 @@ public final class Settings extends InputMethodSettingsFragment
         mAutoCorrectionThresholdPreference =
                 (ListPreference) findPreference(PREF_AUTO_CORRECTION_THRESHOLD);
         mBigramPrediction = (CheckBoxPreference) findPreference(PREF_BIGRAM_PREDICTIONS);
-        mDebugSettingsPreference = findPreference(PREF_DEBUG_SETTINGS);
-        if (mDebugSettingsPreference != null) {
-            final Intent debugSettingsIntent = new Intent(Intent.ACTION_MAIN);
-            debugSettingsIntent.setClassName(
-                    context.getPackageName(), DebugSettings.class.getName());
-            mDebugSettingsPreference.setIntent(debugSettingsIntent);
-        }
-
         ensureConsistencyOfAutoCorrectionSettings();
 
         final PreferenceGroup generalSettings =
@@ -150,6 +139,18 @@ public final class Settings extends InputMethodSettingsFragment
         final PreferenceGroup miscSettings =
                 (PreferenceGroup) findPreference(PREF_MISC_SETTINGS);
 
+        mDebugSettingsPreference = findPreference(PREF_DEBUG_SETTINGS);
+        if (mDebugSettingsPreference != null) {
+            if (ProductionFlag.IS_INTERNAL) {
+                final Intent debugSettingsIntent = new Intent(Intent.ACTION_MAIN);
+                debugSettingsIntent.setClassName(
+                        context.getPackageName(), DebugSettingsActivity.class.getName());
+                mDebugSettingsPreference.setIntent(debugSettingsIntent);
+            } else {
+                miscSettings.removePreference(mDebugSettingsPreference);
+            }
+        }
+
         final boolean showVoiceKeyOption = res.getBoolean(
                 R.bool.config_enable_show_voice_key_option);
         if (!showVoiceKeyOption) {
@@ -207,7 +208,7 @@ public final class Settings extends InputMethodSettingsFragment
                 R.bool.config_gesture_input_enabled_by_build_config);
         final Preference gesturePreviewTrail = findPreference(PREF_GESTURE_PREVIEW_TRAIL);
         final Preference gestureFloatingPreviewText = findPreference(
-                PREF_SHOW_GESTURE_FLOATING_PREVIEW_TEXT);
+                PREF_GESTURE_FLOATING_PREVIEW_TEXT);
         if (!gestureInputEnabledByBuildConfig) {
             miscSettings.removePreference(findPreference(PREF_GESTURE_INPUT));
             miscSettings.removePreference(gesturePreviewTrail);
@@ -218,24 +219,6 @@ public final class Settings extends InputMethodSettingsFragment
             setPreferenceEnabled(gestureFloatingPreviewText, gestureInputEnabledByUser);
         }
 
-        final boolean showUsabilityStudyModeOption =
-                res.getBoolean(R.bool.config_enable_usability_study_mode_option)
-                        || ProductionFlag.IS_EXPERIMENTAL || ENABLE_INTERNAL_SETTINGS;
-        final Preference usabilityStudyPref = findPreference(PREF_USABILITY_STUDY_MODE);
-        if (!showUsabilityStudyModeOption) {
-            if (usabilityStudyPref != null) {
-                miscSettings.removePreference(usabilityStudyPref);
-            }
-        }
-        if (ProductionFlag.IS_EXPERIMENTAL) {
-            if (usabilityStudyPref instanceof CheckBoxPreference) {
-                CheckBoxPreference checkbox = (CheckBoxPreference)usabilityStudyPref;
-                checkbox.setChecked(prefs.getBoolean(PREF_USABILITY_STUDY_MODE,
-                        ResearchLogger.DEFAULT_USABILITY_STUDY_MODE));
-                checkbox.setSummary(R.string.settings_warning_researcher_mode);
-            }
-        }
-
         mKeypressVibrationDurationSettingsPref =
                 (PreferenceScreen) findPreference(PREF_VIBRATION_DURATION_SETTINGS);
         if (mKeypressVibrationDurationSettingsPref != null) {
@@ -304,7 +287,7 @@ public final class Settings extends InputMethodSettingsFragment
                         PREF_GESTURE_INPUT, true);
                 setPreferenceEnabled(findPreference(PREF_GESTURE_PREVIEW_TRAIL),
                         gestureInputEnabledByUser);
-                setPreferenceEnabled(findPreference(PREF_SHOW_GESTURE_FLOATING_PREVIEW_TEXT),
+                setPreferenceEnabled(findPreference(PREF_GESTURE_FLOATING_PREVIEW_TEXT),
                         gestureInputEnabledByUser);
             }
         }
diff --git a/java/src/com/android/inputmethod/latin/SettingsActivity.java b/java/src/com/android/inputmethod/latin/SettingsActivity.java
index 68f8582fc..0d3c8ebb7 100644
--- a/java/src/com/android/inputmethod/latin/SettingsActivity.java
+++ b/java/src/com/android/inputmethod/latin/SettingsActivity.java
@@ -19,7 +19,7 @@ package com.android.inputmethod.latin;
 import android.content.Intent;
 import android.preference.PreferenceActivity;
 
-public class SettingsActivity extends PreferenceActivity {
+public final class SettingsActivity extends PreferenceActivity {
     private static final String DEFAULT_FRAGMENT = Settings.class.getName();
 
     @Override
diff --git a/java/src/com/android/inputmethod/latin/SettingsValues.java b/java/src/com/android/inputmethod/latin/SettingsValues.java
index 9d8379a7a..2a778aa0d 100644
--- a/java/src/com/android/inputmethod/latin/SettingsValues.java
+++ b/java/src/com/android/inputmethod/latin/SettingsValues.java
@@ -178,7 +178,7 @@ public final class SettingsValues {
                 && prefs.getBoolean(Settings.PREF_GESTURE_INPUT, true);
         mGesturePreviewTrailEnabled = prefs.getBoolean(Settings.PREF_GESTURE_PREVIEW_TRAIL, true);
         mGestureFloatingPreviewTextEnabled = prefs.getBoolean(
-                Settings.PREF_SHOW_GESTURE_FLOATING_PREVIEW_TEXT, false);
+                Settings.PREF_GESTURE_FLOATING_PREVIEW_TEXT, true);
         mCorrectionEnabled = mAutoCorrectEnabled && !mInputAttributes.mInputTypeNoAutoCorrect;
         mSuggestionVisibility = createSuggestionVisibility(res);
     }
@@ -254,11 +254,13 @@ public final class SettingsValues {
         return mSymbolsExcludedFromWordSeparators.contains(String.valueOf((char)code));
     }
 
+    // TODO: use "Phantom" instead of "Weak" in this method name
     public boolean isWeakSpaceStripper(final int code) {
         // TODO: this does not work if the code does not fit in a char
         return mWeakSpaceStrippers.contains(String.valueOf((char)code));
     }
 
+    // TODO: use "Phantom" instead of "Weak" in this method name
     public boolean isWeakSpaceSwapper(final int code) {
         // TODO: this does not work if the code does not fit in a char
         return mWeakSpaceSwappers.contains(String.valueOf((char)code));
@@ -410,7 +412,7 @@ public final class SettingsValues {
     // Likewise
     public static boolean getUsabilityStudyMode(final SharedPreferences prefs) {
         // TODO: use mUsabilityStudyMode instead of reading it again here
-        return prefs.getBoolean(Settings.PREF_USABILITY_STUDY_MODE, true);
+        return prefs.getBoolean(DebugSettings.PREF_USABILITY_STUDY_MODE, true);
     }
 
     public static long getLastUserHistoryWriteTime(final SharedPreferences prefs,
diff --git a/java/src/com/android/inputmethod/latin/StringUtils.java b/java/src/com/android/inputmethod/latin/StringUtils.java
index 7b65b7343..043043cef 100644
--- a/java/src/com/android/inputmethod/latin/StringUtils.java
+++ b/java/src/com/android/inputmethod/latin/StringUtils.java
@@ -16,10 +16,9 @@
 
 package com.android.inputmethod.latin;
 
+import android.text.InputType;
 import android.text.TextUtils;
 
-import com.android.inputmethod.keyboard.Keyboard; // For character constants
-
 import java.util.ArrayList;
 import java.util.Locale;
 
@@ -28,30 +27,30 @@ public final class StringUtils {
         // This utility class is not publicly instantiable.
     }
 
-    public static int codePointCount(String text) {
+    public static int codePointCount(final String text) {
         if (TextUtils.isEmpty(text)) return 0;
         return text.codePointCount(0, text.length());
     }
 
-    public static boolean containsInArray(String key, String[] array) {
+    public static boolean containsInArray(final String key, final String[] array) {
         for (final String element : array) {
             if (key.equals(element)) return true;
         }
         return false;
     }
 
-    public static boolean containsInCsv(String key, String csv) {
+    public static boolean containsInCsv(final String key, final String csv) {
         if (TextUtils.isEmpty(csv)) return false;
         return containsInArray(key, csv.split(","));
     }
 
-    public static String appendToCsvIfNotExists(String key, String csv) {
+    public static String appendToCsvIfNotExists(final String key, final String csv) {
         if (TextUtils.isEmpty(csv)) return key;
         if (containsInCsv(key, csv)) return csv;
         return csv + "," + key;
     }
 
-    public static String removeFromCsvIfExists(String key, String csv) {
+    public static String removeFromCsvIfExists(final String key, final String csv) {
         if (TextUtils.isEmpty(csv)) return "";
         final String[] elements = csv.split(",");
         if (!containsInArray(key, elements)) return csv;
@@ -63,82 +62,20 @@ public final class StringUtils {
     }
 
     /**
-     * Returns true if a and b are equal ignoring the case of the character.
-     * @param a first character to check
-     * @param b second character to check
-     * @return {@code true} if a and b are equal, {@code false} otherwise.
-     */
-    public static boolean equalsIgnoreCase(char a, char b) {
-        // Some language, such as Turkish, need testing both cases.
-        return a == b
-                || Character.toLowerCase(a) == Character.toLowerCase(b)
-                || Character.toUpperCase(a) == Character.toUpperCase(b);
-    }
-
-    /**
-     * Returns true if a and b are equal ignoring the case of the characters, including if they are
-     * both null.
-     * @param a first CharSequence to check
-     * @param b second CharSequence to check
-     * @return {@code true} if a and b are equal, {@code false} otherwise.
-     */
-    public static boolean equalsIgnoreCase(CharSequence a, CharSequence b) {
-        if (a == b)
-            return true;  // including both a and b are null.
-        if (a == null || b == null)
-            return false;
-        final int length = a.length();
-        if (length != b.length())
-            return false;
-        for (int i = 0; i < length; i++) {
-            if (!equalsIgnoreCase(a.charAt(i), b.charAt(i)))
-                return false;
-        }
-        return true;
-    }
-
-    /**
-     * Returns true if a and b are equal ignoring the case of the characters, including if a is null
-     * and b is zero length.
-     * @param a CharSequence to check
-     * @param b character array to check
-     * @param offset start offset of array b
-     * @param length length of characters in array b
-     * @return {@code true} if a and b are equal, {@code false} otherwise.
-     * @throws IndexOutOfBoundsException
-     *   if {@code offset < 0 || length < 0 || offset + length > data.length}.
-     * @throws NullPointerException if {@code b == null}.
-     */
-    public static boolean equalsIgnoreCase(CharSequence a, char[] b, int offset, int length) {
-        if (offset < 0 || length < 0 || length > b.length - offset)
-            throw new IndexOutOfBoundsException("array.length=" + b.length + " offset=" + offset
-                    + " length=" + length);
-        if (a == null)
-            return length == 0;  // including a is null and b is zero length.
-        if (a.length() != length)
-            return false;
-        for (int i = 0; i < length; i++) {
-            if (!equalsIgnoreCase(a.charAt(i), b[offset + i]))
-                return false;
-        }
-        return true;
-    }
-
-    /**
      * Remove duplicates from an array of strings.
      *
      * This method will always keep the first occurrence of all strings at their position
      * in the array, removing the subsequent ones.
      */
-    public static void removeDupes(final ArrayList<CharSequence> suggestions) {
+    public static void removeDupes(final ArrayList<String> suggestions) {
         if (suggestions.size() < 2) return;
         int i = 1;
         // Don't cache suggestions.size(), since we may be removing items
         while (i < suggestions.size()) {
-            final CharSequence cur = suggestions.get(i);
+            final String cur = suggestions.get(i);
             // Compare each suggestion with each previous suggestion
             for (int j = 0; j < i; j++) {
-                CharSequence previous = suggestions.get(j);
+                final String previous = suggestions.get(j);
                 if (TextUtils.equals(cur, previous)) {
                     suggestions.remove(i);
                     i--;
@@ -149,7 +86,7 @@ public final class StringUtils {
         }
     }
 
-    public static String toTitleCase(String s, Locale locale) {
+    public static String toTitleCase(final String s, final Locale locale) {
         if (s.length() <= 1) {
             // TODO: is this really correct? Shouldn't this be s.toUpperCase()?
             return s;
@@ -165,21 +102,19 @@ public final class StringUtils {
         return s.toUpperCase(locale).charAt(0) + s.substring(1);
     }
 
+    private static final int[] EMPTY_CODEPOINTS = {};
+
     public static int[] toCodePointArray(final String string) {
-        final char[] characters = string.toCharArray();
-        final int length = characters.length;
-        final int[] codePoints = new int[Character.codePointCount(characters, 0, length)];
+        final int length = string.length();
         if (length <= 0) {
-            return new int[0];
+            return EMPTY_CODEPOINTS;
         }
-        int codePoint = Character.codePointAt(characters, 0);
-        int dsti = 0;
-        for (int srci = Character.charCount(codePoint);
-                srci < length; srci += Character.charCount(codePoint), ++dsti) {
-            codePoints[dsti] = codePoint;
-            codePoint = Character.codePointAt(characters, srci);
+        final int[] codePoints = new int[string.codePointCount(0, length)];
+        int destIndex = 0;
+        for (int index = 0; index < length; index = string.offsetByCodePoints(index, 1)) {
+            codePoints[destIndex] = string.codePointAt(index);
+            destIndex++;
         }
-        codePoints[dsti] = codePoint;
         return codePoints;
     }
 
@@ -237,7 +172,7 @@ public final class StringUtils {
         } else {
             for (i = cs.length(); i > 0; i--) {
                 final char c = cs.charAt(i - 1);
-                if (c != Keyboard.CODE_DOUBLE_QUOTE && c != Keyboard.CODE_SINGLE_QUOTE
+                if (c != Constants.CODE_DOUBLE_QUOTE && c != Constants.CODE_SINGLE_QUOTE
                         && Character.getType(c) != Character.START_PUNCTUATION) {
                     break;
                 }
@@ -250,15 +185,19 @@ public final class StringUtils {
 
         // Step 3 : Search for the start of a paragraph. From the starting point computed in step 2,
         // we go back over any space or tab char sitting there. We find the start of a paragraph
-        // if the first char that's not a space or tab is a start of line (as in, either \n or
-        // start of text).
+        // if the first char that's not a space or tab is a start of line (as in \n, start of text,
+        // or some other similar characters).
         int j = i;
+        char prevChar = Constants.CODE_SPACE;
         if (hasSpaceBefore) --j;
-        while (j > 0 && Character.isWhitespace(cs.charAt(j - 1))) {
+        while (j > 0) {
+            prevChar = cs.charAt(j - 1);
+            if (!Character.isSpaceChar(prevChar) && prevChar != Constants.CODE_TAB) break;
             j--;
         }
-        if (j == 0) {
-            // There is only whitespace between the start of the text and the cursor. Both
+        if (j <= 0 || Character.isWhitespace(prevChar)) {
+            // There are only spacing chars between the start of the paragraph and the cursor,
+            // defined as a isWhitespace() char that is neither a isSpaceChar() nor a tab. Both
             // MODE_WORDS and MODE_SENTENCES should be active.
             return (TextUtils.CAP_MODE_CHARACTERS | TextUtils.CAP_MODE_WORDS
                     | TextUtils.CAP_MODE_SENTENCES) & reqModes;
@@ -292,7 +231,7 @@ public final class StringUtils {
                 // variants of English, the final period is placed within double quotes and maybe
                 // other closing punctuation signs. This is generally not true in other languages.
                 final char c = cs.charAt(j - 1);
-                if (c != Keyboard.CODE_DOUBLE_QUOTE && c != Keyboard.CODE_SINGLE_QUOTE
+                if (c != Constants.CODE_DOUBLE_QUOTE && c != Constants.CODE_SINGLE_QUOTE
                         && Character.getType(c) != Character.END_PUNCTUATION) {
                     break;
                 }
@@ -306,10 +245,10 @@ public final class StringUtils {
         // end of a sentence. If we have a question mark or an exclamation mark, it's the end of
         // a sentence. If it's neither, the only remaining case is the period so we get the opposite
         // case out of the way.
-        if (c == Keyboard.CODE_QUESTION_MARK || c == Keyboard.CODE_EXCLAMATION_MARK) {
+        if (c == Constants.CODE_QUESTION_MARK || c == Constants.CODE_EXCLAMATION_MARK) {
             return (TextUtils.CAP_MODE_CHARACTERS | TextUtils.CAP_MODE_SENTENCES) & reqModes;
         }
-        if (c != Keyboard.CODE_PERIOD || j <= 0) {
+        if (c != Constants.CODE_PERIOD || j <= 0) {
             return (TextUtils.CAP_MODE_CHARACTERS | TextUtils.CAP_MODE_WORDS) & reqModes;
         }
 
@@ -359,7 +298,7 @@ public final class StringUtils {
             case WORD:
                 if (Character.isLetter(c)) {
                     state = WORD;
-                } else if (c == Keyboard.CODE_PERIOD) {
+                } else if (c == Constants.CODE_PERIOD) {
                     state = PERIOD;
                 } else {
                     return caps;
@@ -375,7 +314,7 @@ public final class StringUtils {
             case LETTER:
                 if (Character.isLetter(c)) {
                     state = LETTER;
-                } else if (c == Keyboard.CODE_PERIOD) {
+                } else if (c == Constants.CODE_PERIOD) {
                     state = PERIOD;
                 } else {
                     return noCaps;
diff --git a/java/src/com/android/inputmethod/latin/SubtypeLocale.java b/java/src/com/android/inputmethod/latin/SubtypeLocale.java
index de5f515b0..579f96bb4 100644
--- a/java/src/com/android/inputmethod/latin/SubtypeLocale.java
+++ b/java/src/com/android/inputmethod/latin/SubtypeLocale.java
@@ -30,7 +30,7 @@ import com.android.inputmethod.latin.LocaleUtils.RunInLocale;
 import java.util.HashMap;
 import java.util.Locale;
 
-public class SubtypeLocale {
+public final class SubtypeLocale {
     static final String TAG = SubtypeLocale.class.getSimpleName();
     // This class must be located in the same package as LatinIME.java.
     private static final String RESOURCE_PACKAGE_NAME =
diff --git a/java/src/com/android/inputmethod/latin/SubtypeSwitcher.java b/java/src/com/android/inputmethod/latin/SubtypeSwitcher.java
index c693edcca..8e51a372b 100644
--- a/java/src/com/android/inputmethod/latin/SubtypeSwitcher.java
+++ b/java/src/com/android/inputmethod/latin/SubtypeSwitcher.java
@@ -38,7 +38,7 @@ import java.util.List;
 import java.util.Locale;
 import java.util.Map;
 
-public class SubtypeSwitcher {
+public final class SubtypeSwitcher {
     private static boolean DBG = LatinImeLogger.sDBG;
     private static final String TAG = SubtypeSwitcher.class.getSimpleName();
 
@@ -60,7 +60,7 @@ public class SubtypeSwitcher {
 
     private boolean mIsNetworkConnected;
 
-    static class NeedsToDisplayLanguage {
+    static final class NeedsToDisplayLanguage {
         private int mEnabledSubtypeCount;
         private boolean mIsSystemLanguageSameAsInputLanguage;
 
diff --git a/java/src/com/android/inputmethod/latin/Suggest.java b/java/src/com/android/inputmethod/latin/Suggest.java
index 278c4b9ce..3dc2ba95b 100644
--- a/java/src/com/android/inputmethod/latin/Suggest.java
+++ b/java/src/com/android/inputmethod/latin/Suggest.java
@@ -19,7 +19,7 @@ package com.android.inputmethod.latin;
 import android.content.Context;
 import android.text.TextUtils;
 
-import com.android.inputmethod.keyboard.Keyboard;
+import com.android.inputmethod.annotations.UsedForTesting;
 import com.android.inputmethod.keyboard.ProximityInfo;
 import com.android.inputmethod.latin.SuggestedWords.SuggestedWordInfo;
 
@@ -34,11 +34,11 @@ import java.util.concurrent.ConcurrentHashMap;
  * This class loads a dictionary and provides a list of suggestions for a given sequence of
  * characters. This includes corrections and completions.
  */
-public class Suggest {
+public final class Suggest {
     public static final String TAG = Suggest.class.getSimpleName();
 
     // Session id for
-    // {@link #getSuggestedWords(WordComposer,CharSequence,ProximityInfo,boolean,int)}.
+    // {@link #getSuggestedWords(WordComposer,String,ProximityInfo,boolean,int)}.
     public static final int SESSION_TYPING = 0;
     public static final int SESSION_GESTURE = 1;
 
@@ -71,7 +71,8 @@ public class Suggest {
         mLocale = locale;
     }
 
-    /* package for test */ Suggest(final Context context, final File dictionary,
+    @UsedForTesting
+    Suggest(final Context context, final File dictionary,
             final long startOffset, final long length, final Locale locale) {
         final Dictionary mainDict = DictionaryFactory.createDictionaryForTest(context, dictionary,
                 startOffset, length /* useFullEditDistance */, false, locale);
@@ -138,7 +139,7 @@ public class Suggest {
      * Sets an optional user dictionary resource to be loaded. The user dictionary is consulted
      * before the main dictionary, if set. This refers to the system-managed user dictionary.
      */
-    public void setUserDictionary(UserBinaryDictionary userDictionary) {
+    public void setUserDictionary(final UserBinaryDictionary userDictionary) {
         addOrReplaceDictionary(mDictionaries, Dictionary.TYPE_USER, userDictionary);
     }
 
@@ -147,12 +148,12 @@ public class Suggest {
      * the contacts dictionary by passing null to this method. In this case no contacts dictionary
      * won't be used.
      */
-    public void setContactsDictionary(ContactsBinaryDictionary contactsDictionary) {
+    public void setContactsDictionary(final ContactsBinaryDictionary contactsDictionary) {
         mContactsDict = contactsDictionary;
         addOrReplaceDictionary(mDictionaries, Dictionary.TYPE_CONTACTS, contactsDictionary);
     }
 
-    public void setUserHistoryDictionary(UserHistoryDictionary userHistoryDictionary) {
+    public void setUserHistoryDictionary(final UserHistoryDictionary userHistoryDictionary) {
         addOrReplaceDictionary(mDictionaries, Dictionary.TYPE_USER_HISTORY, userHistoryDictionary);
     }
 
@@ -160,9 +161,9 @@ public class Suggest {
         mAutoCorrectionThreshold = threshold;
     }
 
-    public SuggestedWords getSuggestedWords(
-            final WordComposer wordComposer, CharSequence prevWordForBigram,
-            final ProximityInfo proximityInfo, final boolean isCorrectionEnabled, int sessionId) {
+    public SuggestedWords getSuggestedWords(final WordComposer wordComposer,
+            final String prevWordForBigram, final ProximityInfo proximityInfo,
+            final boolean isCorrectionEnabled, final int sessionId) {
         LatinImeLogger.onStartSuggestion(prevWordForBigram);
         if (wordComposer.isBatchMode()) {
             return getSuggestedWordsForBatchInput(
@@ -174,9 +175,9 @@ public class Suggest {
     }
 
     // Retrieves suggestions for the typing input.
-    private SuggestedWords getSuggestedWordsForTypingInput(
-            final WordComposer wordComposer, CharSequence prevWordForBigram,
-            final ProximityInfo proximityInfo, final boolean isCorrectionEnabled) {
+    private SuggestedWords getSuggestedWordsForTypingInput(final WordComposer wordComposer,
+            final String prevWordForBigram, final ProximityInfo proximityInfo,
+            final boolean isCorrectionEnabled) {
         final int trailingSingleQuotesCount = wordComposer.trailingSingleQuotesCount();
         final BoundedTreeSet suggestionsSet = new BoundedTreeSet(sSuggestedWordInfoComparator,
                 MAX_SUGGESTIONS);
@@ -203,7 +204,7 @@ public class Suggest {
                     wordComposerForLookup, prevWordForBigram, proximityInfo));
         }
 
-        final CharSequence whitelistedWord;
+        final String whitelistedWord;
         if (suggestionsSet.isEmpty()) {
             whitelistedWord = null;
         } else if (SuggestedWordInfo.KIND_WHITELIST != suggestionsSet.first().mKind) {
@@ -287,9 +288,9 @@ public class Suggest {
     }
 
     // Retrieves suggestions for the batch input.
-    private SuggestedWords getSuggestedWordsForBatchInput(
-            final WordComposer wordComposer, CharSequence prevWordForBigram,
-            final ProximityInfo proximityInfo, int sessionId) {
+    private SuggestedWords getSuggestedWordsForBatchInput(final WordComposer wordComposer,
+            final String prevWordForBigram, final ProximityInfo proximityInfo,
+            final int sessionId) {
         final BoundedTreeSet suggestionsSet = new BoundedTreeSet(sSuggestedWordInfoComparator,
                 MAX_SUGGESTIONS);
 
@@ -307,7 +308,7 @@ public class Suggest {
         }
 
         for (SuggestedWordInfo wordInfo : suggestionsSet) {
-            LatinImeLogger.onAddSuggestedWord(wordInfo.mWord.toString(), wordInfo.mSourceDict);
+            LatinImeLogger.onAddSuggestedWord(wordInfo.mWord, wordInfo.mSourceDict);
         }
 
         final ArrayList<SuggestedWordInfo> suggestionsContainer =
@@ -362,7 +363,8 @@ public class Suggest {
         return suggestionsList;
     }
 
-    private static class SuggestedWordInfoComparator implements Comparator<SuggestedWordInfo> {
+    private static final class SuggestedWordInfoComparator
+            implements Comparator<SuggestedWordInfo> {
         // This comparator ranks the word info with the higher frequency first. That's because
         // that's the order we want our elements in.
         @Override
@@ -371,7 +373,7 @@ public class Suggest {
             if (o1.mScore < o2.mScore) return 1;
             if (o1.mCodePointCount < o2.mCodePointCount) return -1;
             if (o1.mCodePointCount > o2.mCodePointCount) return 1;
-            return o1.mWord.toString().compareTo(o2.mWord.toString());
+            return o1.mWord.compareTo(o2.mWord);
         }
     }
     private static final SuggestedWordInfoComparator sSuggestedWordInfoComparator =
@@ -382,16 +384,17 @@ public class Suggest {
             final boolean isFirstCharCapitalized, final int trailingSingleQuotesCount) {
         final StringBuilder sb = new StringBuilder(wordInfo.mWord.length());
         if (isAllUpperCase) {
-            sb.append(wordInfo.mWord.toString().toUpperCase(locale));
+            sb.append(wordInfo.mWord.toUpperCase(locale));
         } else if (isFirstCharCapitalized) {
-            sb.append(StringUtils.toTitleCase(wordInfo.mWord.toString(), locale));
+            sb.append(StringUtils.toTitleCase(wordInfo.mWord, locale));
         } else {
             sb.append(wordInfo.mWord);
         }
         for (int i = trailingSingleQuotesCount - 1; i >= 0; --i) {
-            sb.appendCodePoint(Keyboard.CODE_SINGLE_QUOTE);
+            sb.appendCodePoint(Constants.CODE_SINGLE_QUOTE);
         }
-        return new SuggestedWordInfo(sb, wordInfo.mScore, wordInfo.mKind, wordInfo.mSourceDict);
+        return new SuggestedWordInfo(sb.toString(), wordInfo.mScore, wordInfo.mKind,
+                wordInfo.mSourceDict);
     }
 
     public void close() {
diff --git a/java/src/com/android/inputmethod/latin/SuggestedWords.java b/java/src/com/android/inputmethod/latin/SuggestedWords.java
index d9f48c4a4..572f2906e 100644
--- a/java/src/com/android/inputmethod/latin/SuggestedWords.java
+++ b/java/src/com/android/inputmethod/latin/SuggestedWords.java
@@ -23,7 +23,7 @@ import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.HashSet;
 
-public class SuggestedWords {
+public final class SuggestedWords {
     private static final ArrayList<SuggestedWordInfo> EMPTY_WORD_INFO_LIST =
             CollectionUtils.newArrayList(0);
     public static final SuggestedWords EMPTY = new SuggestedWords(
@@ -53,6 +53,10 @@ public class SuggestedWords {
         mIsPrediction = isPrediction;
     }
 
+    public boolean isEmpty() {
+        return mSuggestedWordInfoList.isEmpty();
+    }
+
     public int size() {
         return mSuggestedWordInfoList.size();
     }
@@ -86,11 +90,14 @@ public class SuggestedWords {
     public static ArrayList<SuggestedWordInfo> getFromApplicationSpecifiedCompletions(
             final CompletionInfo[] infos) {
         final ArrayList<SuggestedWordInfo> result = CollectionUtils.newArrayList();
-        for (CompletionInfo info : infos) {
-            if (null != info && info.getText() != null) {
-                result.add(new SuggestedWordInfo(info.getText(), SuggestedWordInfo.MAX_SCORE,
-                        SuggestedWordInfo.KIND_APP_DEFINED, Dictionary.TYPE_APPLICATION_DEFINED));
-            }
+        for (final CompletionInfo info : infos) {
+            if (info == null) continue;
+            final CharSequence text = info.getText();
+            if (null == text) continue;
+            final SuggestedWordInfo suggestedWordInfo = new SuggestedWordInfo(text.toString(),
+                    SuggestedWordInfo.MAX_SCORE, SuggestedWordInfo.KIND_APP_DEFINED,
+                    Dictionary.TYPE_APPLICATION_DEFINED);
+            result.add(suggestedWordInfo);
         }
         return result;
     }
@@ -98,7 +105,7 @@ public class SuggestedWords {
     // Should get rid of the first one (what the user typed previously) from suggestions
     // and replace it with what the user currently typed.
     public static ArrayList<SuggestedWordInfo> getTypedWordAndPreviousSuggestions(
-            final CharSequence typedWord, final SuggestedWords previousSuggestions) {
+            final String typedWord, final SuggestedWords previousSuggestions) {
         final ArrayList<SuggestedWordInfo> suggestionsList = CollectionUtils.newArrayList();
         final HashSet<String> alreadySeen = CollectionUtils.newHashSet();
         suggestionsList.add(new SuggestedWordInfo(typedWord, SuggestedWordInfo.MAX_SCORE,
@@ -107,7 +114,7 @@ public class SuggestedWords {
         final int previousSize = previousSuggestions.size();
         for (int pos = 1; pos < previousSize; pos++) {
             final SuggestedWordInfo prevWordInfo = previousSuggestions.getWordInfo(pos);
-            final String prevWord = prevWordInfo.mWord.toString();
+            final String prevWord = prevWordInfo.mWord;
             // Filter out duplicate suggestion.
             if (!alreadySeen.contains(prevWord)) {
                 suggestionsList.add(prevWordInfo);
@@ -117,7 +124,7 @@ public class SuggestedWords {
         return suggestionsList;
     }
 
-    public static class SuggestedWordInfo {
+    public static final class SuggestedWordInfo {
         public static final int MAX_SCORE = Integer.MAX_VALUE;
         public static final int KIND_TYPED = 0; // What user typed
         public static final int KIND_CORRECTION = 1; // Simple correction/suggestion
@@ -135,9 +142,9 @@ public class SuggestedWords {
         public final String mSourceDict;
         private String mDebugString = "";
 
-        public SuggestedWordInfo(final CharSequence word, final int score, final int kind,
+        public SuggestedWordInfo(final String word, final int score, final int kind,
                 final String sourceDict) {
-            mWord = word.toString();
+            mWord = word;
             mScore = score;
             mKind = kind;
             mSourceDict = sourceDict;
@@ -145,7 +152,7 @@ public class SuggestedWords {
         }
 
 
-        public void setDebugString(String str) {
+        public void setDebugString(final String str) {
             if (null == str) throw new NullPointerException("Debug info is null");
             mDebugString = str;
         }
@@ -167,7 +174,7 @@ public class SuggestedWords {
             if (TextUtils.isEmpty(mDebugString)) {
                 return mWord;
             } else {
-                return mWord + " (" + mDebugString.toString() + ")";
+                return mWord + " (" + mDebugString + ")";
             }
         }
 
diff --git a/java/src/com/android/inputmethod/latin/SuggestionSpanPickedNotificationReceiver.java b/java/src/com/android/inputmethod/latin/SuggestionSpanPickedNotificationReceiver.java
index 4a3f42d5d..d188fc5ef 100644
--- a/java/src/com/android/inputmethod/latin/SuggestionSpanPickedNotificationReceiver.java
+++ b/java/src/com/android/inputmethod/latin/SuggestionSpanPickedNotificationReceiver.java
@@ -23,7 +23,7 @@ import android.content.Context;
 import android.content.Intent;
 import android.util.Log;
 
-public class SuggestionSpanPickedNotificationReceiver extends BroadcastReceiver {
+public final class SuggestionSpanPickedNotificationReceiver extends BroadcastReceiver {
     private static final boolean DBG = LatinImeLogger.sDBG;
     private static final String TAG =
             SuggestionSpanPickedNotificationReceiver.class.getSimpleName();
diff --git a/java/src/com/android/inputmethod/latin/SynchronouslyLoadedContactsBinaryDictionary.java b/java/src/com/android/inputmethod/latin/SynchronouslyLoadedContactsBinaryDictionary.java
index bdd988df2..ec4dc1436 100644
--- a/java/src/com/android/inputmethod/latin/SynchronouslyLoadedContactsBinaryDictionary.java
+++ b/java/src/com/android/inputmethod/latin/SynchronouslyLoadedContactsBinaryDictionary.java
@@ -24,7 +24,7 @@ import com.android.inputmethod.latin.SuggestedWords.SuggestedWordInfo;
 import java.util.ArrayList;
 import java.util.Locale;
 
-public class SynchronouslyLoadedContactsBinaryDictionary extends ContactsBinaryDictionary {
+public final class SynchronouslyLoadedContactsBinaryDictionary extends ContactsBinaryDictionary {
     private boolean mClosed;
 
     public SynchronouslyLoadedContactsBinaryDictionary(final Context context, final Locale locale) {
@@ -33,13 +33,13 @@ public class SynchronouslyLoadedContactsBinaryDictionary extends ContactsBinaryD
 
     @Override
     public synchronized ArrayList<SuggestedWordInfo> getSuggestions(final WordComposer codes,
-            final CharSequence prevWordForBigrams, final ProximityInfo proximityInfo) {
+            final String prevWordForBigrams, final ProximityInfo proximityInfo) {
         syncReloadDictionaryIfRequired();
         return super.getSuggestions(codes, prevWordForBigrams, proximityInfo);
     }
 
     @Override
-    public synchronized boolean isValidWord(CharSequence word) {
+    public synchronized boolean isValidWord(final String word) {
         syncReloadDictionaryIfRequired();
         return isValidWordInner(word);
     }
diff --git a/java/src/com/android/inputmethod/latin/SynchronouslyLoadedUserBinaryDictionary.java b/java/src/com/android/inputmethod/latin/SynchronouslyLoadedUserBinaryDictionary.java
index b8cfddd4e..4bdaf2039 100644
--- a/java/src/com/android/inputmethod/latin/SynchronouslyLoadedUserBinaryDictionary.java
+++ b/java/src/com/android/inputmethod/latin/SynchronouslyLoadedUserBinaryDictionary.java
@@ -23,7 +23,7 @@ import com.android.inputmethod.latin.SuggestedWords.SuggestedWordInfo;
 
 import java.util.ArrayList;
 
-public class SynchronouslyLoadedUserBinaryDictionary extends UserBinaryDictionary {
+public final class SynchronouslyLoadedUserBinaryDictionary extends UserBinaryDictionary {
 
     public SynchronouslyLoadedUserBinaryDictionary(final Context context, final String locale) {
         this(context, locale, false);
@@ -36,13 +36,13 @@ public class SynchronouslyLoadedUserBinaryDictionary extends UserBinaryDictionar
 
     @Override
     public synchronized ArrayList<SuggestedWordInfo> getSuggestions(final WordComposer codes,
-            final CharSequence prevWordForBigrams, final ProximityInfo proximityInfo) {
+            final String prevWordForBigrams, final ProximityInfo proximityInfo) {
         syncReloadDictionaryIfRequired();
         return super.getSuggestions(codes, prevWordForBigrams, proximityInfo);
     }
 
     @Override
-    public synchronized boolean isValidWord(CharSequence word) {
+    public synchronized boolean isValidWord(final String word) {
         syncReloadDictionaryIfRequired();
         return isValidWordInner(word);
     }
diff --git a/java/src/com/android/inputmethod/latin/TargetApplicationGetter.java b/java/src/com/android/inputmethod/latin/TargetApplicationGetter.java
index 4265309e5..743a8c60f 100644
--- a/java/src/com/android/inputmethod/latin/TargetApplicationGetter.java
+++ b/java/src/com/android/inputmethod/latin/TargetApplicationGetter.java
@@ -22,8 +22,7 @@ import android.content.pm.PackageManager;
 import android.os.AsyncTask;
 import android.util.LruCache;
 
-public class TargetApplicationGetter extends AsyncTask<String, Void, ApplicationInfo> {
-
+public final class TargetApplicationGetter extends AsyncTask<String, Void, ApplicationInfo> {
     private static final int MAX_CACHE_ENTRIES = 64; // arbitrary
     private static LruCache<String, ApplicationInfo> sCache =
             new LruCache<String, ApplicationInfo>(MAX_CACHE_ENTRIES);
@@ -32,6 +31,7 @@ public class TargetApplicationGetter extends AsyncTask<String, Void, Application
         if (null == packageName) return null;
         return sCache.get(packageName);
     }
+
     public static void removeApplicationInfoCache(final String packageName) {
         sCache.remove(packageName);
     }
diff --git a/java/src/com/android/inputmethod/latin/UserBinaryDictionary.java b/java/src/com/android/inputmethod/latin/UserBinaryDictionary.java
index 60e6fa127..00c3cbe0a 100644
--- a/java/src/com/android/inputmethod/latin/UserBinaryDictionary.java
+++ b/java/src/com/android/inputmethod/latin/UserBinaryDictionary.java
@@ -200,7 +200,7 @@ public class UserBinaryDictionary extends ExpandableBinaryDictionary {
         mContext.startActivity(intent);
     }
 
-    private void addWords(Cursor cursor) {
+    private void addWords(final Cursor cursor) {
         // 16 is JellyBean, but we want this to compile against ICS.
         final boolean hasShortcutColumn = android.os.Build.VERSION.SDK_INT >= 16;
         clearFusionDictionary();
diff --git a/java/src/com/android/inputmethod/latin/UserHistoryDictIOUtils.java b/java/src/com/android/inputmethod/latin/UserHistoryDictIOUtils.java
index 4a3d11aa1..787197755 100644
--- a/java/src/com/android/inputmethod/latin/UserHistoryDictIOUtils.java
+++ b/java/src/com/android/inputmethod/latin/UserHistoryDictIOUtils.java
@@ -18,6 +18,7 @@ package com.android.inputmethod.latin;
 
 import android.util.Log;
 
+import com.android.inputmethod.annotations.UsedForTesting;
 import com.android.inputmethod.latin.makedict.BinaryDictIOUtils;
 import com.android.inputmethod.latin.makedict.BinaryDictInputOutput;
 import com.android.inputmethod.latin.makedict.BinaryDictInputOutput.FusionDictionaryBufferInterface;
@@ -38,7 +39,7 @@ import java.util.Map;
  *
  * All the methods in this class are static.
  */
-public class UserHistoryDictIOUtils {
+public final class UserHistoryDictIOUtils {
     private static final String TAG = UserHistoryDictIOUtils.class.getSimpleName();
     private static final boolean DEBUG = false;
 
@@ -100,6 +101,11 @@ public class UserHistoryDictIOUtils {
 
         @Override
         public int limit() {
+            return mBuffer.length - 1;
+        }
+
+        @Override
+        public int capacity() {
             return mBuffer.length;
         }
     }
@@ -110,11 +116,10 @@ public class UserHistoryDictIOUtils {
     public static void writeDictionaryBinary(final OutputStream destination,
             final BigramDictionaryInterface dict, final UserHistoryDictionaryBigramList bigrams,
             final FormatOptions formatOptions) {
-
         final FusionDictionary fusionDict = constructFusionDictionary(dict, bigrams);
-
         try {
             BinaryDictInputOutput.writeDictionaryBinary(destination, fusionDict, formatOptions);
+            Log.d(TAG, "end writing");
         } catch (IOException e) {
             Log.e(TAG, "IO exception while writing file: " + e);
         } catch (UnsupportedFormatException e) {
@@ -125,18 +130,21 @@ public class UserHistoryDictIOUtils {
     /**
      * Constructs a new FusionDictionary from BigramDictionaryInterface.
      */
-    /* packages for test */ static FusionDictionary constructFusionDictionary(
+    @UsedForTesting
+    static FusionDictionary constructFusionDictionary(
             final BigramDictionaryInterface dict, final UserHistoryDictionaryBigramList bigrams) {
-
         final FusionDictionary fusionDict = new FusionDictionary(new Node(),
-                new FusionDictionary.DictionaryOptions(
-                        new HashMap<String,String>(), false, false));
-
+                new FusionDictionary.DictionaryOptions(new HashMap<String, String>(), false,
+                        false));
+        int profTotal = 0;
         for (final String word1 : bigrams.keySet()) {
             final HashMap<String, Byte> word1Bigrams = bigrams.getBigrams(word1);
             for (final String word2 : word1Bigrams.keySet()) {
                 final int freq = dict.getFrequency(word1, word2);
-
+                if (freq == -1) {
+                    // don't add this bigram.
+                    continue;
+                }
                 if (DEBUG) {
                     if (word1 == null) {
                         Log.d(TAG, "add unigram: " + word2 + "," + Integer.toString(freq));
@@ -144,17 +152,22 @@ public class UserHistoryDictIOUtils {
                         Log.d(TAG, "add bigram: " + word1
                                 + "," + word2 + "," + Integer.toString(freq));
                     }
+                    profTotal++;
                 }
-
                 if (word1 == null) { // unigram
                     fusionDict.add(word2, freq, null, false /* isNotAWord */);
                 } else { // bigram
+                    if (FusionDictionary.findWordInTree(fusionDict.mRoot, word1) == null) {
+                        fusionDict.add(word1, 2, null, false /* isNotAWord */);
+                    }
                     fusionDict.setBigram(word1, word2, freq);
                 }
                 bigrams.updateBigram(word1, word2, (byte)freq);
             }
         }
-
+        if (DEBUG) {
+            Log.d(TAG, "add " + profTotal + "words");
+        }
         return fusionDict;
     }
 
@@ -166,32 +179,31 @@ public class UserHistoryDictIOUtils {
         final Map<Integer, String> unigrams = CollectionUtils.newTreeMap();
         final Map<Integer, Integer> frequencies = CollectionUtils.newTreeMap();
         final Map<Integer, ArrayList<PendingAttribute>> bigrams = CollectionUtils.newTreeMap();
-
         try {
             BinaryDictIOUtils.readUnigramsAndBigramsBinary(buffer, unigrams, frequencies,
                     bigrams);
-            addWordsFromWordMap(unigrams, frequencies, bigrams, dict);
         } catch (IOException e) {
             Log.e(TAG, "IO exception while reading file: " + e);
         } catch (UnsupportedFormatException e) {
             Log.e(TAG, "Unsupported format: " + e);
+        } catch (ArrayIndexOutOfBoundsException e) {
+            Log.e(TAG, "ArrayIndexOutOfBoundsException while reading file: " + e);
         }
+        addWordsFromWordMap(unigrams, frequencies, bigrams, dict);
     }
 
     /**
      * Adds all unigrams and bigrams in maps to OnAddWordListener.
      */
-    /* package for test */ static void addWordsFromWordMap(final Map<Integer, String> unigrams,
+    @UsedForTesting
+    static void addWordsFromWordMap(final Map<Integer, String> unigrams,
             final Map<Integer, Integer> frequencies,
             final Map<Integer, ArrayList<PendingAttribute>> bigrams, final OnAddWordListener to) {
-
         for (Map.Entry<Integer, String> entry : unigrams.entrySet()) {
             final String word1 = entry.getValue();
             final int unigramFrequency = frequencies.get(entry.getKey());
             to.setUnigram(word1, null, unigramFrequency);
-
             final ArrayList<PendingAttribute> attrList = bigrams.get(entry.getKey());
-
             if (attrList != null) {
                 for (final PendingAttribute attr : attrList) {
                     to.setBigram(word1, unigrams.get(attr.mAddress),
diff --git a/java/src/com/android/inputmethod/latin/UserHistoryDictionary.java b/java/src/com/android/inputmethod/latin/UserHistoryDictionary.java
index 683ee4f5c..4fd9bfafb 100644
--- a/java/src/com/android/inputmethod/latin/UserHistoryDictionary.java
+++ b/java/src/com/android/inputmethod/latin/UserHistoryDictionary.java
@@ -16,24 +16,26 @@
 
 package com.android.inputmethod.latin;
 
-import android.content.ContentValues;
 import android.content.Context;
 import android.content.SharedPreferences;
-import android.database.Cursor;
-import android.database.sqlite.SQLiteDatabase;
-import android.database.sqlite.SQLiteOpenHelper;
-import android.database.sqlite.SQLiteQueryBuilder;
 import android.os.AsyncTask;
-import android.provider.BaseColumns;
 import android.util.Log;
 
+import com.android.inputmethod.annotations.UsedForTesting;
 import com.android.inputmethod.keyboard.ProximityInfo;
 import com.android.inputmethod.latin.SuggestedWords.SuggestedWordInfo;
+import com.android.inputmethod.latin.UserHistoryDictIOUtils.BigramDictionaryInterface;
+import com.android.inputmethod.latin.UserHistoryDictIOUtils.OnAddWordListener;
 import com.android.inputmethod.latin.UserHistoryForgettingCurveUtils.ForgettingCurveParams;
+import com.android.inputmethod.latin.makedict.FormatSpec.FormatOptions;
 
+import java.io.File;
+import java.io.FileInputStream;
+import java.io.FileNotFoundException;
+import java.io.FileOutputStream;
+import java.io.IOException;
 import java.lang.ref.SoftReference;
 import java.util.ArrayList;
-import java.util.HashMap;
 import java.util.concurrent.ConcurrentHashMap;
 import java.util.concurrent.locks.ReentrantLock;
 
@@ -41,47 +43,29 @@ import java.util.concurrent.locks.ReentrantLock;
  * Locally gathers stats about the words user types and various other signals like auto-correction
  * cancellation or manual picks. This allows the keyboard to adapt to the typist over time.
  */
-public class UserHistoryDictionary extends ExpandableDictionary {
-    private static final String TAG = "UserHistoryDictionary";
+public final class UserHistoryDictionary extends ExpandableDictionary {
+    private static final String TAG = UserHistoryDictionary.class.getSimpleName();
+    private static final String NAME = UserHistoryDictionary.class.getSimpleName();
     public static final boolean DBG_SAVE_RESTORE = false;
     public static final boolean DBG_STRESS_TEST = false;
     public static final boolean DBG_ALWAYS_WRITE = false;
     public static final boolean PROFILE_SAVE_RESTORE = LatinImeLogger.sDBG;
 
+    private static final FormatOptions VERSION3 = new FormatOptions(3,
+            true /* supportsDynamicUpdate */);
+
     /** Any pair being typed or picked */
     private static final int FREQUENCY_FOR_TYPED = 2;
 
     /** Maximum number of pairs. Pruning will start when databases goes above this number. */
-    public static final int sMaxHistoryBigrams = 10000;
+    public static final int MAX_HISTORY_BIGRAMS = 10000;
 
     /**
      * When it hits maximum bigram pair, it will delete until you are left with
      * only (sMaxHistoryBigrams - sDeleteHistoryBigrams) pairs.
      * Do not keep this number small to avoid deleting too often.
      */
-    public static final int sDeleteHistoryBigrams = 1000;
-
-    /**
-     * Database version should increase if the database structure changes
-     */
-    private static final int DATABASE_VERSION = 1;
-
-    private static final String DATABASE_NAME = "userbigram_dict.db";
-
-    /** Name of the words table in the database */
-    private static final String MAIN_TABLE_NAME = "main";
-    // TODO: Consume less space by using a unique id for locale instead of the whole
-    // 2-5 character string.
-    private static final String MAIN_COLUMN_ID = BaseColumns._ID;
-    private static final String MAIN_COLUMN_WORD1 = "word1";
-    private static final String MAIN_COLUMN_WORD2 = "word2";
-    private static final String MAIN_COLUMN_LOCALE = "locale";
-
-    /** Name of the frequency table in the database */
-    private static final String FREQ_TABLE_NAME = "frequency";
-    private static final String FREQ_COLUMN_ID = BaseColumns._ID;
-    private static final String FREQ_COLUMN_PAIR_ID = "pair_id";
-    private static final String COLUMN_FORGETTING_CURVE_VALUE = "freq";
+    public static final int DELETE_HISTORY_BIGRAMS = 1000;
 
     /** Locale for which this user history dictionary is storing words */
     private final String mLocale;
@@ -91,29 +75,13 @@ public class UserHistoryDictionary extends ExpandableDictionary {
     private final ReentrantLock mBigramListLock = new ReentrantLock();
     private final SharedPreferences mPrefs;
 
-    private final static HashMap<String, String> sDictProjectionMap;
-    private final static ConcurrentHashMap<String, SoftReference<UserHistoryDictionary>>
-            sLangDictCache = CollectionUtils.newConcurrentHashMap();
-
-    static {
-        sDictProjectionMap = CollectionUtils.newHashMap();
-        sDictProjectionMap.put(MAIN_COLUMN_ID, MAIN_COLUMN_ID);
-        sDictProjectionMap.put(MAIN_COLUMN_WORD1, MAIN_COLUMN_WORD1);
-        sDictProjectionMap.put(MAIN_COLUMN_WORD2, MAIN_COLUMN_WORD2);
-        sDictProjectionMap.put(MAIN_COLUMN_LOCALE, MAIN_COLUMN_LOCALE);
-
-        sDictProjectionMap.put(FREQ_COLUMN_ID, FREQ_COLUMN_ID);
-        sDictProjectionMap.put(FREQ_COLUMN_PAIR_ID, FREQ_COLUMN_PAIR_ID);
-        sDictProjectionMap.put(COLUMN_FORGETTING_CURVE_VALUE, COLUMN_FORGETTING_CURVE_VALUE);
-    }
-
-    private static DatabaseHelper sOpenHelper = null;
+    // Should always be false except when we use this class for test
+    @UsedForTesting boolean isTest = false;
 
-    public String getLocale() {
-        return mLocale;
-    }
+    private static final ConcurrentHashMap<String, SoftReference<UserHistoryDictionary>>
+            sLangDictCache = CollectionUtils.newConcurrentHashMap();
 
-    public synchronized static UserHistoryDictionary getInstance(
+    public static synchronized UserHistoryDictionary getInstance(
             final Context context, final String locale, final SharedPreferences sp) {
         if (sLangDictCache.containsKey(locale)) {
             final SoftReference<UserHistoryDictionary> ref = sLangDictCache.get(locale);
@@ -136,9 +104,6 @@ public class UserHistoryDictionary extends ExpandableDictionary {
         super(context, Dictionary.TYPE_USER_HISTORY);
         mLocale = locale;
         mPrefs = sp;
-        if (sOpenHelper == null) {
-            sOpenHelper = new DatabaseHelper(getContext());
-        }
         if (mLocale != null && mLocale.length() > 1) {
             loadDictionary();
         }
@@ -158,7 +123,7 @@ public class UserHistoryDictionary extends ExpandableDictionary {
 
     @Override
     protected ArrayList<SuggestedWordInfo> getWordsInner(final WordComposer composer,
-            final CharSequence prevWord, final ProximityInfo proximityInfo) {
+            final String prevWord, final ProximityInfo proximityInfo) {
         // Inhibit suggestions (not predictions) for user history for now. Removing this method
         // is enough to use it through the standard ExpandableDictionary way.
         return null;
@@ -168,7 +133,7 @@ public class UserHistoryDictionary extends ExpandableDictionary {
      * Return whether the passed charsequence is in the dictionary.
      */
     @Override
-    public synchronized boolean isValidWord(final CharSequence word) {
+    public synchronized boolean isValidWord(final String word) {
         // TODO: figure out what is the correct thing to do here.
         return false;
     }
@@ -181,7 +146,7 @@ public class UserHistoryDictionary extends ExpandableDictionary {
      * context, as in beginning of a sentence for example.
      * The second word may not be null (a NullPointerException would be thrown).
      */
-    public int addToUserHistory(final String word1, String word2, boolean isValid) {
+    public int addToUserHistory(final String word1, final String word2, final boolean isValid) {
         if (word2.length() >= BinaryDictionary.MAX_WORD_LENGTH ||
                 (word1 != null && word1.length() >= BinaryDictionary.MAX_WORD_LENGTH)) {
             return -1;
@@ -190,6 +155,7 @@ public class UserHistoryDictionary extends ExpandableDictionary {
             try {
                 super.addWord(
                         word2, null /* the "shortcut" parameter is null */, FREQUENCY_FOR_TYPED);
+                mBigramList.addBigram(null, word2, (byte)FREQUENCY_FOR_TYPED);
                 // Do not insert a word as a bigram of itself
                 if (word2.equals(word1)) {
                     return 0;
@@ -210,7 +176,7 @@ public class UserHistoryDictionary extends ExpandableDictionary {
         return -1;
     }
 
-    public boolean cancelAddingUserHistory(String word1, String word2) {
+    public boolean cancelAddingUserHistory(final String word1, final String word2) {
         if (mBigramListLock.tryLock()) {
             try {
                 if (mBigramList.removeBigram(word1, word2)) {
@@ -227,11 +193,8 @@ public class UserHistoryDictionary extends ExpandableDictionary {
      * Schedules a background thread to write any pending words to the database.
      */
     private void flushPendingWrites() {
-        if (mBigramListLock.isLocked()) {
-            return;
-        }
         // Create a background thread to write the pending entries
-        new UpdateDbTask(sOpenHelper, mBigramList, mLocale, this, mPrefs).execute();
+        new UpdateBinaryTask(mBigramList, mLocale, this, mPrefs, getContext()).execute();
     }
 
     @Override
@@ -245,6 +208,8 @@ public class UserHistoryDictionary extends ExpandableDictionary {
         }
     }
 
+    private int profTotal;
+
     private void loadDictionaryAsyncLocked() {
         if (DBG_STRESS_TEST) {
             try {
@@ -257,343 +222,184 @@ public class UserHistoryDictionary extends ExpandableDictionary {
         final long last = SettingsValues.getLastUserHistoryWriteTime(mPrefs, mLocale);
         final boolean initializing = last == 0;
         final long now = System.currentTimeMillis();
-        // Load the words that correspond to the current input locale
-        final Cursor cursor = query(MAIN_COLUMN_LOCALE + "=?", new String[] { mLocale });
-        if (null == cursor) return;
-        try {
-            // TODO: Call SQLiteDataBase.beginTransaction / SQLiteDataBase.endTransaction
-            if (cursor.moveToFirst()) {
-                final int word1Index = cursor.getColumnIndex(MAIN_COLUMN_WORD1);
-                final int word2Index = cursor.getColumnIndex(MAIN_COLUMN_WORD2);
-                final int fcIndex = cursor.getColumnIndex(COLUMN_FORGETTING_CURVE_VALUE);
-                while (!cursor.isAfterLast()) {
-                    final String word1 = cursor.getString(word1Index);
-                    final String word2 = cursor.getString(word2Index);
-                    final int fc = cursor.getInt(fcIndex);
+        profTotal = 0;
+        final String fileName = NAME + "." + mLocale + ".dict";
+        final ExpandableDictionary dictionary = this;
+        final OnAddWordListener listener = new OnAddWordListener() {
+            @Override
+            public void setUnigram(final String word, final String shortcutTarget,
+                    final int frequency) {
+                profTotal++;
+                if (DBG_SAVE_RESTORE) {
+                    Log.d(TAG, "load unigram: " + word + "," + frequency);
+                }
+                dictionary.addWord(word, shortcutTarget, frequency);
+                mBigramList.addBigram(null, word, (byte)frequency);
+            }
+
+            @Override
+            public void setBigram(final String word1, final String word2, final int frequency) {
+                if (word1.length() < BinaryDictionary.MAX_WORD_LENGTH
+                        && word2.length() < BinaryDictionary.MAX_WORD_LENGTH) {
+                    profTotal++;
                     if (DBG_SAVE_RESTORE) {
-                        Log.d(TAG, "--- Load user history: " + word1 + ", " + word2 + ","
-                                + mLocale + "," + this);
-                    }
-                    // Safeguard against adding really long words. Stack may overflow due
-                    // to recursive lookup
-                    if (null == word1) {
-                        super.addWord(word2, null /* shortcut */, fc);
-                    } else if (word1.length() < BinaryDictionary.MAX_WORD_LENGTH
-                            && word2.length() < BinaryDictionary.MAX_WORD_LENGTH) {
-                        super.setBigramAndGetFrequency(
-                                word1, word2, initializing ? new ForgettingCurveParams(true)
-                                : new ForgettingCurveParams(fc, now, last));
+                        Log.d(TAG, "load bigram: " + word1 + "," + word2 + "," + frequency);
                     }
-                    mBigramList.addBigram(word1, word2, (byte)fc);
-                    cursor.moveToNext();
+                    dictionary.setBigramAndGetFrequency(
+                            word1, word2, initializing ? new ForgettingCurveParams(true)
+                            : new ForgettingCurveParams(frequency, now, last));
                 }
+                mBigramList.addBigram(word1, word2, (byte)frequency);
             }
+        };
+
+        // Load the dictionary from binary file
+        FileInputStream inStream = null;
+        try {
+            final File file = new File(getContext().getFilesDir(), fileName);
+            final byte[] buffer = new byte[(int)file.length()];
+            inStream = new FileInputStream(file);
+            inStream.read(buffer);
+            UserHistoryDictIOUtils.readDictionaryBinary(
+                    new UserHistoryDictIOUtils.ByteArrayWrapper(buffer), listener);
+        } catch (FileNotFoundException e) {
+            Log.e(TAG, "when loading: file not found" + e);
+        } catch (IOException e) {
+            Log.e(TAG, "IOException when open bytebuffer: " + e);
         } finally {
-            cursor.close();
+            if (inStream != null) {
+                try {
+                    inStream.close();
+                } catch (IOException e) {
+                    // do nothing
+                }
+            }
             if (PROFILE_SAVE_RESTORE) {
                 final long diff = System.currentTimeMillis() - now;
-                Log.w(TAG, "PROF: Load User HistoryDictionary: "
-                        + mLocale + ", " + diff + "ms.");
+                Log.d(TAG, "PROF: Load UserHistoryDictionary: "
+                        + mLocale + ", " + diff + "ms. load " + profTotal + "entries.");
             }
         }
     }
 
     /**
-     * Query the database
-     */
-    private static Cursor query(String selection, String[] selectionArgs) {
-        SQLiteQueryBuilder qb = new SQLiteQueryBuilder();
-
-        // main INNER JOIN frequency ON (main._id=freq.pair_id)
-        qb.setTables(MAIN_TABLE_NAME + " INNER JOIN " + FREQ_TABLE_NAME + " ON ("
-                + MAIN_TABLE_NAME + "." + MAIN_COLUMN_ID + "=" + FREQ_TABLE_NAME + "."
-                + FREQ_COLUMN_PAIR_ID +")");
-
-        qb.setProjectionMap(sDictProjectionMap);
-
-        // Get the database and run the query
-        try {
-            SQLiteDatabase db = sOpenHelper.getReadableDatabase();
-            Cursor c = qb.query(db,
-                    new String[] {
-                            MAIN_COLUMN_WORD1, MAIN_COLUMN_WORD2, COLUMN_FORGETTING_CURVE_VALUE },
-                    selection, selectionArgs, null, null, null);
-            return c;
-        } catch (android.database.sqlite.SQLiteCantOpenDatabaseException e) {
-            // Can't open the database : presumably we can't access storage. That may happen
-            // when the device is wedged; do a best effort to still start the keyboard.
-            return null;
-        }
-    }
-
-    /**
-     * This class helps open, create, and upgrade the database file.
-     */
-    private static class DatabaseHelper extends SQLiteOpenHelper {
-
-        DatabaseHelper(Context context) {
-            super(context, DATABASE_NAME, null, DATABASE_VERSION);
-        }
-
-        @Override
-        public void onCreate(SQLiteDatabase db) {
-            db.execSQL("PRAGMA foreign_keys = ON;");
-            db.execSQL("CREATE TABLE " + MAIN_TABLE_NAME + " ("
-                    + MAIN_COLUMN_ID + " INTEGER PRIMARY KEY,"
-                    + MAIN_COLUMN_WORD1 + " TEXT,"
-                    + MAIN_COLUMN_WORD2 + " TEXT,"
-                    + MAIN_COLUMN_LOCALE + " TEXT"
-                    + ");");
-            db.execSQL("CREATE TABLE " + FREQ_TABLE_NAME + " ("
-                    + FREQ_COLUMN_ID + " INTEGER PRIMARY KEY,"
-                    + FREQ_COLUMN_PAIR_ID + " INTEGER,"
-                    + COLUMN_FORGETTING_CURVE_VALUE + " INTEGER,"
-                    + "FOREIGN KEY(" + FREQ_COLUMN_PAIR_ID + ") REFERENCES " + MAIN_TABLE_NAME
-                    + "(" + MAIN_COLUMN_ID + ")" + " ON DELETE CASCADE"
-                    + ");");
-        }
-
-        @Override
-        public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
-            Log.w(TAG, "Upgrading database from version " + oldVersion + " to "
-                    + newVersion + ", which will destroy all old data");
-            db.execSQL("DROP TABLE IF EXISTS " + MAIN_TABLE_NAME);
-            db.execSQL("DROP TABLE IF EXISTS " + FREQ_TABLE_NAME);
-            onCreate(db);
-        }
-    }
-
-    /**
-     * Async task to write pending words to the database so that it stays in sync with
-     * the in-memory trie.
+     * Async task to write pending words to the binarydicts.
      */
-    private static class UpdateDbTask extends AsyncTask<Void, Void, Void> {
+    private static final class UpdateBinaryTask extends AsyncTask<Void, Void, Void>
+            implements BigramDictionaryInterface {
         private final UserHistoryDictionaryBigramList mBigramList;
-        private final DatabaseHelper mDbHelper;
+        private final boolean mAddLevel0Bigrams;
         private final String mLocale;
         private final UserHistoryDictionary mUserHistoryDictionary;
         private final SharedPreferences mPrefs;
+        private final Context mContext;
 
-        public UpdateDbTask(
-                DatabaseHelper openHelper, UserHistoryDictionaryBigramList pendingWrites,
-                String locale, UserHistoryDictionary dict, SharedPreferences prefs) {
+        public UpdateBinaryTask(final UserHistoryDictionaryBigramList pendingWrites,
+                final String locale, final UserHistoryDictionary dict,
+                final SharedPreferences prefs, final Context context) {
             mBigramList = pendingWrites;
             mLocale = locale;
-            mDbHelper = openHelper;
             mUserHistoryDictionary = dict;
             mPrefs = prefs;
-        }
-
-        /** Prune any old data if the database is getting too big. */
-        private static void checkPruneData(SQLiteDatabase db) {
-            db.execSQL("PRAGMA foreign_keys = ON;");
-            Cursor c = db.query(FREQ_TABLE_NAME, new String[] { FREQ_COLUMN_PAIR_ID },
-                    null, null, null, null, null);
-            try {
-                int totalRowCount = c.getCount();
-                // prune out old data if we have too much data
-                if (totalRowCount > sMaxHistoryBigrams) {
-                    int numDeleteRows = (totalRowCount - sMaxHistoryBigrams)
-                            + sDeleteHistoryBigrams;
-                    int pairIdColumnId = c.getColumnIndex(FREQ_COLUMN_PAIR_ID);
-                    c.moveToFirst();
-                    int count = 0;
-                    while (count < numDeleteRows && !c.isAfterLast()) {
-                        String pairId = c.getString(pairIdColumnId);
-                        // Deleting from MAIN table will delete the frequencies
-                        // due to FOREIGN KEY .. ON DELETE CASCADE
-                        db.delete(MAIN_TABLE_NAME, MAIN_COLUMN_ID + "=?",
-                            new String[] { pairId });
-                        c.moveToNext();
-                        count++;
-                    }
-                }
-            } finally {
-                c.close();
-            }
+            mContext = context;
+            mAddLevel0Bigrams = mBigramList.size() <= MAX_HISTORY_BIGRAMS;
         }
 
         @Override
-        protected Void doInBackground(Void... v) {
-            SQLiteDatabase db = null;
-            if (mUserHistoryDictionary.mBigramListLock.tryLock()) {
+        protected Void doInBackground(final Void... v) {
+            if (mUserHistoryDictionary.isTest) {
+                // If isTest == true, wait until the lock is released.
+                mUserHistoryDictionary.mBigramListLock.lock();
                 try {
-                    try {
-                        db = mDbHelper.getWritableDatabase();
-                    } catch (android.database.sqlite.SQLiteCantOpenDatabaseException e) {
-                        // If we can't open the db, don't do anything. Exit through the next test
-                        // for non-nullity of the db variable.
-                    }
-                    if (null == db) {
-                        // Not much we can do. Just exit.
-                        return null;
-                    }
-                    db.beginTransaction();
-                    return doLoadTaskLocked(db);
+                    doWriteTaskLocked();
                 } finally {
-                    if (db != null) {
-                        db.endTransaction();
-                    }
                     mUserHistoryDictionary.mBigramListLock.unlock();
                 }
+            } else if (mUserHistoryDictionary.mBigramListLock.tryLock()) {
+                doWriteTaskLocked();
             }
             return null;
         }
 
-        private Void doLoadTaskLocked(SQLiteDatabase db) {
+        private void doWriteTaskLocked() {
             if (DBG_STRESS_TEST) {
                 try {
                     Log.w(TAG, "Start stress in closing: " + mLocale);
                     Thread.sleep(15000);
                     Log.w(TAG, "End stress in closing");
                 } catch (InterruptedException e) {
+                    Log.e(TAG, "In stress test: " + e);
                 }
             }
+
             final long now = PROFILE_SAVE_RESTORE ? System.currentTimeMillis() : 0;
-            int profTotal = 0;
-            int profInsert = 0;
-            int profDelete = 0;
-            db.execSQL("PRAGMA foreign_keys = ON;");
-            final boolean addLevel0Bigram = mBigramList.size() <= sMaxHistoryBigrams;
-
-            // Write all the entries to the db
-            for (String word1 : mBigramList.keySet()) {
-                final HashMap<String, Byte> word1Bigrams = mBigramList.getBigrams(word1);
-                for (String word2 : word1Bigrams.keySet()) {
-                    if (PROFILE_SAVE_RESTORE) {
-                        ++profTotal;
-                    }
-                    // Get new frequency. Do not insert unigrams/bigrams which freq is "-1".
-                    final int freq; // -1, or 0~255
-                    if (word1 == null) { // unigram
-                        freq = FREQUENCY_FOR_TYPED;
-                        final byte prevFc = word1Bigrams.get(word2);
-                        if (prevFc == FREQUENCY_FOR_TYPED) {
-                            // No need to update since we found no changes for this entry.
-                            // Just skip to the next entry.
-                            if (DBG_SAVE_RESTORE) {
-                                Log.d(TAG, "Skip update user history: " + word1 + "," + word2
-                                        + "," + prevFc);
-                            }
-                            if (!DBG_ALWAYS_WRITE) {
-                                continue;
-                            }
-                        }
-                    } else { // bigram
-                        final NextWord nw = mUserHistoryDictionary.getBigramWord(word1, word2);
-                        if (nw != null) {
-                            final ForgettingCurveParams fcp = nw.getFcParams();
-                            final byte prevFc = word1Bigrams.get(word2);
-                            final byte fc = (byte)fcp.getFc();
-                            final boolean isValid = fcp.isValid();
-                            if (prevFc > 0 && prevFc == fc) {
-                                // No need to update since we found no changes for this entry.
-                                // Just skip to the next entry.
-                                if (DBG_SAVE_RESTORE) {
-                                    Log.d(TAG, "Skip update user history: " + word1 + ","
-                                            + word2 + "," + prevFc);
-                                }
-                                if (!DBG_ALWAYS_WRITE) {
-                                    continue;
-                                } else {
-                                    freq = fc;
-                                }
-                            } else if (UserHistoryForgettingCurveUtils.
-                                    needsToSave(fc, isValid, addLevel0Bigram)) {
-                                freq = fc;
-                            } else {
-                                // Delete this entry
-                                freq = -1;
-                            }
-                        } else {
-                            // Delete this entry
-                            freq = -1;
-                        }
-                    }
-                    // TODO: this process of making a text search for each pair each time
-                    // is terribly inefficient. Optimize this.
-                    // Find pair id
-                    Cursor c = null;
+            final String fileName = NAME + "." + mLocale + ".dict";
+            final File file = new File(mContext.getFilesDir(), fileName);
+            FileOutputStream out = null;
+
+            try {
+                out = new FileOutputStream(file);
+                UserHistoryDictIOUtils.writeDictionaryBinary(out, this, mBigramList, VERSION3);
+                out.flush();
+                out.close();
+            } catch (IOException e) {
+                Log.e(TAG, "IO Exception while writing file: " + e);
+            } finally {
+                if (out != null) {
                     try {
-                        if (null != word1) {
-                            c = db.query(MAIN_TABLE_NAME, new String[] { MAIN_COLUMN_ID },
-                                    MAIN_COLUMN_WORD1 + "=? AND " + MAIN_COLUMN_WORD2 + "=? AND "
-                                            + MAIN_COLUMN_LOCALE + "=?",
-                                            new String[] { word1, word2, mLocale }, null, null,
-                                            null);
-                        } else {
-                            c = db.query(MAIN_TABLE_NAME, new String[] { MAIN_COLUMN_ID },
-                                    MAIN_COLUMN_WORD1 + " IS NULL AND " + MAIN_COLUMN_WORD2
-                                    + "=? AND " + MAIN_COLUMN_LOCALE + "=?",
-                                    new String[] { word2, mLocale }, null, null, null);
-                        }
-
-                        final int pairId;
-                        if (c.moveToFirst()) {
-                            if (PROFILE_SAVE_RESTORE) {
-                                ++profDelete;
-                            }
-                            // Delete existing pair
-                            pairId = c.getInt(c.getColumnIndex(MAIN_COLUMN_ID));
-                            db.delete(FREQ_TABLE_NAME, FREQ_COLUMN_PAIR_ID + "=?",
-                                    new String[] { Integer.toString(pairId) });
-                        } else {
-                            // Create new pair
-                            Long pairIdLong = db.insert(MAIN_TABLE_NAME, null,
-                                    getContentValues(word1, word2, mLocale));
-                            pairId = pairIdLong.intValue();
-                        }
-                        // Eliminate freq == 0 because that word is profanity.
-                        if (freq > 0) {
-                            if (PROFILE_SAVE_RESTORE) {
-                                ++profInsert;
-                            }
-                            if (DBG_SAVE_RESTORE) {
-                                Log.d(TAG, "--- Save user history: " + word1 + ", " + word2
-                                        + mLocale + "," + this);
-                            }
-                            // Insert new frequency
-                            db.insert(FREQ_TABLE_NAME, null,
-                                    getFrequencyContentValues(pairId, freq));
-                            // Update an existing bigram entry in mBigramList too in order to
-                            // synchronize the SQL DB and mBigramList.
-                            mBigramList.updateBigram(word1, word2, (byte)freq);
-                        }
-                    } finally {
-                        if (c != null) {
-                            c.close();
-                        }
+                        out.close();
+                    } catch (IOException e) {
+                        // ignore
                     }
                 }
             }
 
-            checkPruneData(db);
-            // Save the timestamp after we finish writing the SQL DB.
+            // Save the timestamp after we finish writing the binary dictionary.
             SettingsValues.setLastUserHistoryWriteTime(mPrefs, mLocale);
             if (PROFILE_SAVE_RESTORE) {
                 final long diff = System.currentTimeMillis() - now;
-                Log.w(TAG, "PROF: Write User HistoryDictionary: " + mLocale + ", "+ diff
-                        + "ms. Total: " + profTotal + ". Insert: " + profInsert + ". Delete: "
-                        + profDelete);
+                Log.w(TAG, "PROF: Write User HistoryDictionary: " + mLocale + ", " + diff + "ms.");
             }
-            db.setTransactionSuccessful();
-            return null;
         }
 
-        private static ContentValues getContentValues(String word1, String word2, String locale) {
-            ContentValues values = new ContentValues(3);
-            values.put(MAIN_COLUMN_WORD1, word1);
-            values.put(MAIN_COLUMN_WORD2, word2);
-            values.put(MAIN_COLUMN_LOCALE, locale);
-            return values;
+        @Override
+        public int getFrequency(final String word1, final String word2) {
+            final int freq;
+            if (word1 == null) { // unigram
+                freq = FREQUENCY_FOR_TYPED;
+                final byte prevFc = mBigramList.getBigrams(word1).get(word2);
+            } else { // bigram
+                final NextWord nw = mUserHistoryDictionary.getBigramWord(word1, word2);
+                if (nw != null) {
+                    final ForgettingCurveParams fcp = nw.getFcParams();
+                    final byte prevFc = mBigramList.getBigrams(word1).get(word2);
+                    final byte fc = fcp.getFc();
+                    final boolean isValid = fcp.isValid();
+                    if (prevFc > 0 && prevFc == fc) {
+                        freq = ((int)fc) & 0xFF;
+                    } else if (UserHistoryForgettingCurveUtils.
+                            needsToSave(fc, isValid, mAddLevel0Bigrams)) {
+                        freq = ((int)fc) & 0xFF;
+                    } else {
+                        // Delete this entry
+                        freq = -1;
+                    }
+                } else {
+                    // Delete this entry
+                    freq = -1;
+                }
+            }
+            return freq;
         }
+    }
 
-        private static ContentValues getFrequencyContentValues(int pairId, int frequency) {
-           ContentValues values = new ContentValues(2);
-           values.put(FREQ_COLUMN_PAIR_ID, pairId);
-           values.put(COLUMN_FORGETTING_CURVE_VALUE, frequency);
-           return values;
+    @UsedForTesting
+    void forceAddWordForTest(final String word1, final String word2, final boolean isValid) {
+        mBigramListLock.lock();
+        try {
+            addToUserHistory(word1, word2, isValid);
+        } finally {
+            mBigramListLock.unlock();
         }
     }
-
 }
diff --git a/java/src/com/android/inputmethod/latin/UserHistoryDictionaryBigramList.java b/java/src/com/android/inputmethod/latin/UserHistoryDictionaryBigramList.java
index bb0f5429a..df44948f9 100644
--- a/java/src/com/android/inputmethod/latin/UserHistoryDictionaryBigramList.java
+++ b/java/src/com/android/inputmethod/latin/UserHistoryDictionaryBigramList.java
@@ -26,7 +26,7 @@ import java.util.Set;
  * All bigrams including stale ones in SQL DB should be stored in this class to avoid adding stale
  * bigrams when we write to the SQL DB.
  */
-public class UserHistoryDictionaryBigramList {
+public final class UserHistoryDictionaryBigramList {
     public static final byte FORGETTING_CURVE_INITIAL_VALUE = 0;
     private static final String TAG = UserHistoryDictionaryBigramList.class.getSimpleName();
     private static final HashMap<String, Byte> EMPTY_BIGRAM_MAP = CollectionUtils.newHashMap();
diff --git a/java/src/com/android/inputmethod/latin/UserHistoryForgettingCurveUtils.java b/java/src/com/android/inputmethod/latin/UserHistoryForgettingCurveUtils.java
index 3d3bd980c..9053d709b 100644
--- a/java/src/com/android/inputmethod/latin/UserHistoryForgettingCurveUtils.java
+++ b/java/src/com/android/inputmethod/latin/UserHistoryForgettingCurveUtils.java
@@ -36,7 +36,7 @@ public final class UserHistoryForgettingCurveUtils {
         // This utility class is not publicly instantiable.
     }
 
-    public static class ForgettingCurveParams {
+    public static final class ForgettingCurveParams {
         private byte mFc;
         long mLastTouchedTime = 0;
         private final boolean mIsValid;
@@ -195,7 +195,7 @@ public final class UserHistoryForgettingCurveUtils {
         return (elapsedTime < ELAPSED_TIME_MAX - 1 || level > 0);
     }
 
-    private static class MathUtils {
+    private static final class MathUtils {
         public static final int[][] SCORE_TABLE = new int[FC_LEVEL_MAX][ELAPSED_TIME_MAX + 1];
         static {
             for (int i = 0; i < FC_LEVEL_MAX; ++i) {
diff --git a/java/src/com/android/inputmethod/latin/WordComposer.java b/java/src/com/android/inputmethod/latin/WordComposer.java
index 275ebf305..daff442f3 100644
--- a/java/src/com/android/inputmethod/latin/WordComposer.java
+++ b/java/src/com/android/inputmethod/latin/WordComposer.java
@@ -24,7 +24,7 @@ import java.util.Arrays;
 /**
  * A place to store the currently composing word with information such as adjacent key codes as well
  */
-public class WordComposer {
+public final class WordComposer {
     private static final int N = BinaryDictionary.MAX_WORD_LENGTH;
 
     public static final int CAPS_MODE_OFF = 0;
@@ -38,7 +38,7 @@ public class WordComposer {
     private int[] mPrimaryKeyCodes;
     private final InputPointers mInputPointers = new InputPointers(N);
     private final StringBuilder mTypedWord;
-    private CharSequence mAutoCorrection;
+    private String mAutoCorrection;
     private boolean mIsResumed;
     private boolean mIsBatchMode;
 
@@ -64,7 +64,7 @@ public class WordComposer {
         refreshSize();
     }
 
-    public WordComposer(WordComposer source) {
+    public WordComposer(final WordComposer source) {
         mPrimaryKeyCodes = Arrays.copyOf(source.mPrimaryKeyCodes, source.mPrimaryKeyCodes.length);
         mTypedWord = new StringBuilder(source.mTypedWord);
         mInputPointers.copy(source.mInputPointers);
@@ -121,7 +121,8 @@ public class WordComposer {
         return mInputPointers;
     }
 
-    private static boolean isFirstCharCapitalized(int index, int codePoint, boolean previous) {
+    private static boolean isFirstCharCapitalized(final int index, final int codePoint,
+            final boolean previous) {
         if (index == 0) return Character.isUpperCase(codePoint);
         return previous && !Character.isUpperCase(codePoint);
     }
@@ -129,12 +130,12 @@ public class WordComposer {
     /**
      * Add a new keystroke, with the pressed key's code point with the touch point coordinates.
      */
-    public void add(int primaryCode, int keyX, int keyY) {
+    public void add(final int primaryCode, final int keyX, final int keyY) {
         final int newIndex = size();
         mTypedWord.appendCodePoint(primaryCode);
         refreshSize();
         if (newIndex < BinaryDictionary.MAX_WORD_LENGTH) {
-            mPrimaryKeyCodes[newIndex] = primaryCode >= Keyboard.CODE_SPACE
+            mPrimaryKeyCodes[newIndex] = primaryCode >= Constants.CODE_SPACE
                     ? Character.toLowerCase(primaryCode) : primaryCode;
             // In the batch input mode, the {@code mInputPointers} holds batch input points and
             // shouldn't be overridden by the "typed key" coordinates
@@ -148,7 +149,7 @@ public class WordComposer {
                 newIndex, primaryCode, mIsFirstCharCapitalized);
         if (Character.isUpperCase(primaryCode)) mCapsCount++;
         if (Character.isDigit(primaryCode)) mDigitsCount++;
-        if (Keyboard.CODE_SINGLE_QUOTE == primaryCode) {
+        if (Constants.CODE_SINGLE_QUOTE == primaryCode) {
             ++mTrailingSingleQuotesCount;
         } else {
             mTrailingSingleQuotesCount = 0;
@@ -156,12 +157,12 @@ public class WordComposer {
         mAutoCorrection = null;
     }
 
-    public void setBatchInputPointers(InputPointers batchPointers) {
+    public void setBatchInputPointers(final InputPointers batchPointers) {
         mInputPointers.set(batchPointers);
         mIsBatchMode = true;
     }
 
-    public void setBatchInputWord(CharSequence word) {
+    public void setBatchInputWord(final String word) {
         reset();
         mIsBatchMode = true;
         final int length = word.length();
@@ -177,14 +178,16 @@ public class WordComposer {
      * Internal method to retrieve reasonable proximity info for a character.
      */
     private void addKeyInfo(final int codePoint, final Keyboard keyboard) {
-        final Key key = keyboard.getKey(codePoint);
-        if (key != null) {
-            final int x = key.mX + key.mWidth / 2;
-            final int y = key.mY + key.mHeight / 2;
-            add(codePoint, x, y);
-            return;
+        final int x, y;
+        final Key key;
+        if (keyboard != null && (key = keyboard.getKey(codePoint)) != null) {
+            x = key.mX + key.mWidth / 2;
+            y = key.mY + key.mHeight / 2;
+        } else {
+            x = Constants.NOT_A_COORDINATE;
+            y = Constants.NOT_A_COORDINATE;
         }
-        add(codePoint, Constants.NOT_A_COORDINATE, Constants.NOT_A_COORDINATE);
+        add(codePoint, x, y);
     }
 
     /**
@@ -195,7 +198,7 @@ public class WordComposer {
         reset();
         final int length = word.length();
         for (int i = 0; i < length; i = Character.offsetByCodePoints(word, i, 1)) {
-            int codePoint = Character.codePointAt(word, i);
+            final int codePoint = Character.codePointAt(word, i);
             addKeyInfo(codePoint, keyboard);
         }
         mIsResumed = true;
@@ -233,7 +236,7 @@ public class WordComposer {
             int i = mTypedWord.length();
             while (i > 0) {
                 i = mTypedWord.offsetByCodePoints(i, -1);
-                if (Keyboard.CODE_SINGLE_QUOTE != mTypedWord.codePointAt(i)) break;
+                if (Constants.CODE_SINGLE_QUOTE != mTypedWord.codePointAt(i)) break;
                 ++mTrailingSingleQuotesCount;
             }
         }
@@ -319,14 +322,14 @@ public class WordComposer {
     /**
      * Sets the auto-correction for this word.
      */
-    public void setAutoCorrection(final CharSequence correction) {
+    public void setAutoCorrection(final String correction) {
         mAutoCorrection = correction;
     }
 
     /**
      * @return the auto-correction for this word, or null if none.
      */
-    public CharSequence getAutoCorrectionOrNull() {
+    public String getAutoCorrectionOrNull() {
         return mAutoCorrection;
     }
 
@@ -339,7 +342,7 @@ public class WordComposer {
 
     // `type' should be one of the LastComposedWord.COMMIT_TYPE_* constants above.
     public LastComposedWord commitWord(final int type, final String committedWord,
-            final String separatorString, final CharSequence prevWord) {
+            final String separatorString, final String prevWord) {
         // Note: currently, we come here whenever we commit a word. If it's a MANUAL_PICK
         // or a DECIDED_WORD we may cancel the commit later; otherwise, we should deactivate
         // the last composed word to ensure this does not happen.
diff --git a/java/src/com/android/inputmethod/latin/WordListInfo.java b/java/src/com/android/inputmethod/latin/WordListInfo.java
index 54f04d78f..095320e25 100644
--- a/java/src/com/android/inputmethod/latin/WordListInfo.java
+++ b/java/src/com/android/inputmethod/latin/WordListInfo.java
@@ -19,7 +19,7 @@ package com.android.inputmethod.latin;
 /**
  * Information container for a word list.
  */
-public class WordListInfo {
+public final class WordListInfo {
     public final String mId;
     public final String mLocale;
     public WordListInfo(final String id, final String locale) {
diff --git a/java/src/com/android/inputmethod/latin/XmlParseUtils.java b/java/src/com/android/inputmethod/latin/XmlParseUtils.java
index b5cbaf19e..75dc68f1d 100644
--- a/java/src/com/android/inputmethod/latin/XmlParseUtils.java
+++ b/java/src/com/android/inputmethod/latin/XmlParseUtils.java
@@ -36,28 +36,28 @@ public final class XmlParseUtils {
     }
 
     @SuppressWarnings("serial")
-    public static class IllegalStartTag extends ParseException {
+    public static final class IllegalStartTag extends ParseException {
         public IllegalStartTag(XmlPullParser parser, String parent) {
             super("Illegal start tag " + parser.getName() + " in " + parent, parser);
         }
     }
 
     @SuppressWarnings("serial")
-    public static class IllegalEndTag extends ParseException {
+    public static final class IllegalEndTag extends ParseException {
         public IllegalEndTag(XmlPullParser parser, String parent) {
             super("Illegal end tag " + parser.getName() + " in " + parent, parser);
         }
     }
 
     @SuppressWarnings("serial")
-    public static class IllegalAttribute extends ParseException {
+    public static final class IllegalAttribute extends ParseException {
         public IllegalAttribute(XmlPullParser parser, String attribute) {
             super("Tag " + parser.getName() + " has illegal attribute " + attribute, parser);
         }
     }
 
     @SuppressWarnings("serial")
-    public static class NonEmptyTag extends ParseException{
+    public static final class NonEmptyTag extends ParseException{
         public NonEmptyTag(String tag, XmlPullParser parser) {
             super(tag + " must be empty tag", parser);
         }
diff --git a/java/src/com/android/inputmethod/latin/makedict/BinaryDictIOUtils.java b/java/src/com/android/inputmethod/latin/makedict/BinaryDictIOUtils.java
index 7a1b9dcb7..ee0e9cd7e 100644
--- a/java/src/com/android/inputmethod/latin/makedict/BinaryDictIOUtils.java
+++ b/java/src/com/android/inputmethod/latin/makedict/BinaryDictIOUtils.java
@@ -16,21 +16,34 @@
 
 package com.android.inputmethod.latin.makedict;
 
+import com.android.inputmethod.annotations.UsedForTesting;
 import com.android.inputmethod.latin.Constants;
+import com.android.inputmethod.latin.makedict.BinaryDictInputOutput.CharEncoding;
 import com.android.inputmethod.latin.makedict.BinaryDictInputOutput.FusionDictionaryBufferInterface;
 import com.android.inputmethod.latin.makedict.FormatSpec.FileHeader;
 import com.android.inputmethod.latin.makedict.FormatSpec.FormatOptions;
 import com.android.inputmethod.latin.makedict.FusionDictionary.CharGroup;
+import com.android.inputmethod.latin.makedict.FusionDictionary.WeightedString;
 
 import java.io.IOException;
+import java.io.OutputStream;
 import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.Iterator;
 import java.util.Map;
 import java.util.Stack;
 
-public class BinaryDictIOUtils {
+public final class BinaryDictIOUtils {
     private static final boolean DBG = false;
+    private static final int MSB24 = 0x800000;
+    private static final int SINT24_MAX = 0x7FFFFF;
+    private static final int MAX_JUMPS = 10000;
 
-    private static class Position {
+    private BinaryDictIOUtils() {
+        // This utility class is not publicly instantiable.
+    }
+
+    private static final class Position {
         public static final int NOT_READ_GROUPCOUNT = -1;
 
         public int mAddress;
@@ -77,7 +90,10 @@ public class BinaryDictIOUtils {
                 p.mAddress += BinaryDictInputOutput.getGroupCountSize(p.mNumOfCharGroup);
                 p.mPosition = 0;
             }
-
+            if (p.mNumOfCharGroup == 0) {
+                stack.pop();
+                continue;
+            }
             CharGroupInfo info = BinaryDictInputOutput.readCharGroup(buffer,
                     p.mAddress - headerSize, formatOptions);
             for (int i = 0; i < info.mCharacters.length; ++i) {
@@ -85,20 +101,36 @@ public class BinaryDictIOUtils {
             }
             p.mPosition++;
 
-            if (info.mFrequency != FusionDictionary.CharGroup.NOT_A_TERMINAL) { // found word
+            final boolean isMovedGroup = BinaryDictInputOutput.isMovedGroup(info.mFlags,
+                    formatOptions);
+            final boolean isDeletedGroup = BinaryDictInputOutput.isDeletedGroup(info.mFlags,
+                    formatOptions);
+            if (!isMovedGroup && !isDeletedGroup
+                    && info.mFrequency != FusionDictionary.CharGroup.NOT_A_TERMINAL) {// found word
                 words.put(info.mOriginalAddress, new String(pushedChars, 0, index));
                 frequencies.put(info.mOriginalAddress, info.mFrequency);
                 if (info.mBigrams != null) bigrams.put(info.mOriginalAddress, info.mBigrams);
             }
 
             if (p.mPosition == p.mNumOfCharGroup) {
-                stack.pop();
+                if (formatOptions.mSupportsDynamicUpdate) {
+                    final int forwardLinkAddress = buffer.readUnsignedInt24();
+                    if (forwardLinkAddress != FormatSpec.NO_FORWARD_LINK_ADDRESS) {
+                        // the node has a forward link.
+                        p.mNumOfCharGroup = Position.NOT_READ_GROUPCOUNT;
+                        p.mAddress = forwardLinkAddress;
+                    } else {
+                        stack.pop();
+                    }
+                } else {
+                    stack.pop();
+                }
             } else {
                 // the node has more groups.
                 p.mAddress = buffer.position();
             }
 
-            if (BinaryDictInputOutput.hasChildrenAddress(info.mChildrenAddress)) {
+            if (!isMovedGroup && BinaryDictInputOutput.hasChildrenAddress(info.mChildrenAddress)) {
                 Position childrenPos = new Position(info.mChildrenAddress + headerSize, index);
                 stack.push(childrenPos);
             }
@@ -136,6 +168,7 @@ public class BinaryDictIOUtils {
      * @throws IOException
      * @throws UnsupportedFormatException
      */
+    @UsedForTesting
     public static int getTerminalPosition(final FusionDictionaryBufferInterface buffer,
             final String word) throws IOException, UnsupportedFormatException {
         if (word == null) return FormatSpec.NOT_VALID_WORD;
@@ -146,48 +179,802 @@ public class BinaryDictIOUtils {
         final int wordLen = word.codePointCount(0, word.length());
         for (int depth = 0; depth < Constants.Dictionary.MAX_WORD_LENGTH; ++depth) {
             if (wordPos >= wordLen) return FormatSpec.NOT_VALID_WORD;
-            int groupOffset = buffer.position() - header.mHeaderSize;
+
+            do {
+                final int charGroupCount = BinaryDictInputOutput.readCharGroupCount(buffer);
+                boolean foundNextCharGroup = false;
+                for (int i = 0; i < charGroupCount; ++i) {
+                    final int charGroupPos = buffer.position();
+                    final CharGroupInfo currentInfo = BinaryDictInputOutput.readCharGroup(buffer,
+                            buffer.position(), header.mFormatOptions);
+                    final boolean isMovedGroup =
+                            BinaryDictInputOutput.isMovedGroup(currentInfo.mFlags,
+                                    header.mFormatOptions);
+                    final boolean isDeletedGroup =
+                            BinaryDictInputOutput.isDeletedGroup(currentInfo.mFlags,
+                                    header.mFormatOptions);
+                    if (isMovedGroup) continue;
+                    boolean same = true;
+                    for (int p = 0, j = word.offsetByCodePoints(0, wordPos);
+                            p < currentInfo.mCharacters.length;
+                            ++p, j = word.offsetByCodePoints(j, 1)) {
+                        if (wordPos + p >= wordLen
+                                || word.codePointAt(j) != currentInfo.mCharacters[p]) {
+                            same = false;
+                            break;
+                        }
+                    }
+
+                    if (same) {
+                        // found the group matches the word.
+                        if (wordPos + currentInfo.mCharacters.length == wordLen) {
+                            if (currentInfo.mFrequency == CharGroup.NOT_A_TERMINAL
+                                    || isDeletedGroup) {
+                                return FormatSpec.NOT_VALID_WORD;
+                            } else {
+                                return charGroupPos;
+                            }
+                        }
+                        wordPos += currentInfo.mCharacters.length;
+                        if (currentInfo.mChildrenAddress == FormatSpec.NO_CHILDREN_ADDRESS) {
+                            return FormatSpec.NOT_VALID_WORD;
+                        }
+                        foundNextCharGroup = true;
+                        buffer.position(currentInfo.mChildrenAddress);
+                        break;
+                    }
+                }
+
+                // If we found the next char group, it is under the file pointer.
+                // But if not, we are at the end of this node so we expect to have
+                // a forward link address that we need to consult and possibly resume
+                // search on the next node in the linked list.
+                if (foundNextCharGroup) break;
+                if (!header.mFormatOptions.mSupportsDynamicUpdate) {
+                    return FormatSpec.NOT_VALID_WORD;
+                }
+
+                final int forwardLinkAddress = buffer.readUnsignedInt24();
+                if (forwardLinkAddress == FormatSpec.NO_FORWARD_LINK_ADDRESS) {
+                    return FormatSpec.NOT_VALID_WORD;
+                }
+                buffer.position(forwardLinkAddress);
+            } while(true);
+        }
+        return FormatSpec.NOT_VALID_WORD;
+    }
+
+    private static int markAsDeleted(final int flags) {
+        return (flags & (~FormatSpec.MASK_GROUP_ADDRESS_TYPE)) | FormatSpec.FLAG_IS_DELETED;
+    }
+
+    /**
+     * Delete the word from the binary file.
+     *
+     * @param buffer the buffer to write.
+     * @param word the word we delete
+     * @throws IOException
+     * @throws UnsupportedFormatException
+     */
+    @UsedForTesting
+    public static void deleteWord(final FusionDictionaryBufferInterface buffer,
+            final String word) throws IOException, UnsupportedFormatException {
+        buffer.position(0);
+        final FileHeader header = BinaryDictInputOutput.readHeader(buffer);
+        final int wordPosition = getTerminalPosition(buffer, word);
+        if (wordPosition == FormatSpec.NOT_VALID_WORD) return;
+
+        buffer.position(wordPosition);
+        final int flags = buffer.readUnsignedByte();
+        buffer.position(wordPosition);
+        buffer.put((byte)markAsDeleted(flags));
+    }
+
+    /**
+     * @return the size written, in bytes. Always 3 bytes.
+     */
+    private static int writeSInt24ToBuffer(final FusionDictionaryBufferInterface buffer,
+            final int value) {
+        final int absValue = Math.abs(value);
+        buffer.put((byte)(((value < 0 ? 0x80 : 0) | (absValue >> 16)) & 0xFF));
+        buffer.put((byte)((absValue >> 8) & 0xFF));
+        buffer.put((byte)(absValue & 0xFF));
+        return 3;
+    }
+
+    /**
+     * @return the size written, in bytes. Always 3 bytes.
+     */
+    private static int writeSInt24ToStream(final OutputStream destination, final int value)
+            throws IOException {
+        final int absValue = Math.abs(value);
+        destination.write((byte)(((value < 0 ? 0x80 : 0) | (absValue >> 16)) & 0xFF));
+        destination.write((byte)((absValue >> 8) & 0xFF));
+        destination.write((byte)(absValue & 0xFF));
+        return 3;
+    }
+
+    /**
+     * @return the size written, in bytes. 1, 2, or 3 bytes.
+     */
+    private static int writeVariableAddress(final OutputStream destination, final int value)
+            throws IOException {
+        switch (BinaryDictInputOutput.getByteSize(value)) {
+        case 1:
+            destination.write((byte)value);
+            break;
+        case 2:
+            destination.write((byte)(0xFF & (value >> 8)));
+            destination.write((byte)(0xFF & value));
+            break;
+        case 3:
+            destination.write((byte)(0xFF & (value >> 16)));
+            destination.write((byte)(0xFF & (value >> 8)));
+            destination.write((byte)(0xFF & value));
+            break;
+        }
+        return BinaryDictInputOutput.getByteSize(value);
+    }
+
+    /**
+     * Update a parent address in a CharGroup that is referred to by groupOriginAddress.
+     *
+     * @param buffer the buffer to write.
+     * @param groupOriginAddress the address of the group.
+     * @param newParentAddress the absolute address of the parent.
+     * @param formatOptions file format options.
+     */
+    public static void updateParentAddress(final FusionDictionaryBufferInterface buffer,
+            final int groupOriginAddress, final int newParentAddress,
+            final FormatOptions formatOptions) {
+        final int originalPosition = buffer.position();
+        buffer.position(groupOriginAddress);
+        if (!formatOptions.mSupportsDynamicUpdate) {
+            throw new RuntimeException("this file format does not support parent addresses");
+        }
+        final int flags = buffer.readUnsignedByte();
+        if (BinaryDictInputOutput.isMovedGroup(flags, formatOptions)) {
+            // if the group is moved, the parent address is stored in the destination group.
+            // We are guaranteed to process the destination group later, so there is no need to
+            // update anything here.
+            buffer.position(originalPosition);
+            return;
+        }
+        if (DBG) {
+            MakedictLog.d("update parent address flags=" + flags + ", " + groupOriginAddress);
+        }
+        final int parentOffset = newParentAddress - groupOriginAddress;
+        writeSInt24ToBuffer(buffer, parentOffset);
+        buffer.position(originalPosition);
+    }
+
+    private static void skipCharGroup(final FusionDictionaryBufferInterface buffer,
+            final FormatOptions formatOptions) {
+        final int flags = buffer.readUnsignedByte();
+        BinaryDictInputOutput.readParentAddress(buffer, formatOptions);
+        skipString(buffer, (flags & FormatSpec.FLAG_HAS_MULTIPLE_CHARS) != 0);
+        BinaryDictInputOutput.readChildrenAddress(buffer, flags, formatOptions);
+        if ((flags & FormatSpec.FLAG_IS_TERMINAL) != 0) buffer.readUnsignedByte();
+        if ((flags & FormatSpec.FLAG_HAS_SHORTCUT_TARGETS) != 0) {
+            final int shortcutsSize = buffer.readUnsignedShort();
+            buffer.position(buffer.position() + shortcutsSize
+                    - FormatSpec.GROUP_SHORTCUT_LIST_SIZE_SIZE);
+        }
+        if ((flags & FormatSpec.FLAG_HAS_BIGRAMS) != 0) {
+            int bigramCount = 0;
+            while (bigramCount++ < FormatSpec.MAX_BIGRAMS_IN_A_GROUP) {
+                final int bigramFlags = buffer.readUnsignedByte();
+                switch (bigramFlags & FormatSpec.MASK_ATTRIBUTE_ADDRESS_TYPE) {
+                    case FormatSpec.FLAG_ATTRIBUTE_ADDRESS_TYPE_ONEBYTE:
+                        buffer.readUnsignedByte();
+                        break;
+                    case FormatSpec.FLAG_ATTRIBUTE_ADDRESS_TYPE_TWOBYTES:
+                        buffer.readUnsignedShort();
+                        break;
+                    case FormatSpec.FLAG_ATTRIBUTE_ADDRESS_TYPE_THREEBYTES:
+                        buffer.readUnsignedInt24();
+                        break;
+                }
+                if ((bigramFlags & FormatSpec.FLAG_ATTRIBUTE_HAS_NEXT) == 0) break;
+            }
+            if (bigramCount >= FormatSpec.MAX_BIGRAMS_IN_A_GROUP) {
+                throw new RuntimeException("Too many bigrams in a group.");
+            }
+        }
+    }
+
+    /**
+     * Update parent addresses in a Node that is referred to by nodeOriginAddress.
+     *
+     * @param buffer the buffer to be modified.
+     * @param nodeOriginAddress the address of a modified Node.
+     * @param newParentAddress the address to be written.
+     * @param formatOptions file format options.
+     */
+    public static void updateParentAddresses(final FusionDictionaryBufferInterface buffer,
+            final int nodeOriginAddress, final int newParentAddress,
+            final FormatOptions formatOptions) {
+        final int originalPosition = buffer.position();
+        buffer.position(nodeOriginAddress);
+        do {
+            final int count = BinaryDictInputOutput.readCharGroupCount(buffer);
+            for (int i = 0; i < count; ++i) {
+                updateParentAddress(buffer, buffer.position(), newParentAddress, formatOptions);
+                skipCharGroup(buffer, formatOptions);
+            }
+            final int forwardLinkAddress = buffer.readUnsignedInt24();
+            buffer.position(forwardLinkAddress);
+        } while (formatOptions.mSupportsDynamicUpdate
+                && buffer.position() != FormatSpec.NO_FORWARD_LINK_ADDRESS);
+        buffer.position(originalPosition);
+    }
+
+    private static void skipString(final FusionDictionaryBufferInterface buffer,
+            final boolean hasMultipleChars) {
+        if (hasMultipleChars) {
+            int character = CharEncoding.readChar(buffer);
+            while (character != FormatSpec.INVALID_CHARACTER) {
+                character = CharEncoding.readChar(buffer);
+            }
+        } else {
+            CharEncoding.readChar(buffer);
+        }
+    }
+
+    /**
+     * Write a string to a stream.
+     *
+     * @param destination the stream to write.
+     * @param word the string to be written.
+     * @return the size written, in bytes.
+     * @throws IOException
+     */
+    private static int writeString(final OutputStream destination, final String word)
+            throws IOException {
+        int size = 0;
+        final int length = word.length();
+        for (int i = 0; i < length; i = word.offsetByCodePoints(i, 1)) {
+            final int codePoint = word.codePointAt(i);
+            if (CharEncoding.getCharSize(codePoint) == 1) {
+                destination.write((byte)codePoint);
+                size++;
+            } else {
+                destination.write((byte)(0xFF & (codePoint >> 16)));
+                destination.write((byte)(0xFF & (codePoint >> 8)));
+                destination.write((byte)(0xFF & codePoint));
+                size += 3;
+            }
+        }
+        destination.write((byte)FormatSpec.GROUP_CHARACTERS_TERMINATOR);
+        size += FormatSpec.GROUP_TERMINATOR_SIZE;
+        return size;
+    }
+
+    /**
+     * Update a children address in a CharGroup that is addressed by groupOriginAddress.
+     *
+     * @param buffer the buffer to write.
+     * @param groupOriginAddress the address of the group.
+     * @param newChildrenAddress the absolute address of the child.
+     * @param formatOptions file format options.
+     */
+    public static void updateChildrenAddress(final FusionDictionaryBufferInterface buffer,
+            final int groupOriginAddress, final int newChildrenAddress,
+            final FormatOptions formatOptions) {
+        final int originalPosition = buffer.position();
+        buffer.position(groupOriginAddress);
+        final int flags = buffer.readUnsignedByte();
+        final int parentAddress = BinaryDictInputOutput.readParentAddress(buffer, formatOptions);
+        skipString(buffer, (flags & FormatSpec.FLAG_HAS_MULTIPLE_CHARS) != 0);
+        if ((flags & FormatSpec.FLAG_IS_TERMINAL) != 0) buffer.readUnsignedByte();
+        final int childrenOffset = newChildrenAddress == FormatSpec.NO_CHILDREN_ADDRESS
+                ? FormatSpec.NO_CHILDREN_ADDRESS : newChildrenAddress - buffer.position();
+        writeSInt24ToBuffer(buffer, childrenOffset);
+        buffer.position(originalPosition);
+    }
+
+    /**
+     * Write a char group to an output stream.
+     * A char group is an in-memory representation of a node in trie.
+     * A char group info is an on-disk representation of a node.
+     *
+     * @param destination the stream to write.
+     * @param info the char group info to be written.
+     * @return the size written, in bytes.
+     */
+    public static int writeCharGroup(final OutputStream destination, final CharGroupInfo info)
+            throws IOException {
+        int size = FormatSpec.GROUP_FLAGS_SIZE;
+        destination.write((byte)info.mFlags);
+        final int parentOffset = info.mParentAddress == FormatSpec.NO_PARENT_ADDRESS ?
+                FormatSpec.NO_PARENT_ADDRESS : info.mParentAddress - info.mOriginalAddress;
+        size += writeSInt24ToStream(destination, parentOffset);
+
+        for (int i = 0; i < info.mCharacters.length; ++i) {
+            if (CharEncoding.getCharSize(info.mCharacters[i]) == 1) {
+                destination.write((byte)info.mCharacters[i]);
+                size++;
+            } else {
+                size += writeSInt24ToStream(destination, info.mCharacters[i]);
+            }
+        }
+        if (info.mCharacters.length > 1) {
+            destination.write((byte)FormatSpec.GROUP_CHARACTERS_TERMINATOR);
+            size++;
+        }
+
+        if ((info.mFlags & FormatSpec.FLAG_IS_TERMINAL) != 0) {
+            destination.write((byte)info.mFrequency);
+            size++;
+        }
+
+        if (DBG) {
+            MakedictLog.d("writeCharGroup origin=" + info.mOriginalAddress + ", size=" + size
+                    + ", child=" + info.mChildrenAddress + ", characters ="
+                    + new String(info.mCharacters, 0, info.mCharacters.length));
+        }
+        final int childrenOffset = info.mChildrenAddress == FormatSpec.NO_CHILDREN_ADDRESS ?
+                0 : info.mChildrenAddress - (info.mOriginalAddress + size);
+        writeSInt24ToStream(destination, childrenOffset);
+        size += FormatSpec.SIGNED_CHILDREN_ADDRESS_SIZE;
+
+        if (info.mShortcutTargets != null && info.mShortcutTargets.size() > 0) {
+            final int shortcutListSize =
+                    BinaryDictInputOutput.getShortcutListSize(info.mShortcutTargets);
+            destination.write((byte)(shortcutListSize >> 8));
+            destination.write((byte)(shortcutListSize & 0xFF));
+            size += 2;
+            final Iterator<WeightedString> shortcutIterator = info.mShortcutTargets.iterator();
+            while (shortcutIterator.hasNext()) {
+                final WeightedString target = shortcutIterator.next();
+                destination.write((byte)BinaryDictInputOutput.makeShortcutFlags(
+                        shortcutIterator.hasNext(), target.mFrequency));
+                size++;
+                size += writeString(destination, target.mWord);
+            }
+        }
+
+        if (info.mBigrams != null) {
+            // TODO: Consolidate this code with the code that computes the size of the bigram list
+            //        in BinaryDictionaryInputOutput#computeActualNodeSize
+            for (int i = 0; i < info.mBigrams.size(); ++i) {
+
+                final int bigramFrequency = info.mBigrams.get(i).mFrequency;
+                int bigramFlags = (i < info.mBigrams.size() - 1)
+                        ? FormatSpec.FLAG_ATTRIBUTE_HAS_NEXT : 0;
+                size++;
+                final int bigramOffset = info.mBigrams.get(i).mAddress - (info.mOriginalAddress
+                        + size);
+                bigramFlags |= (bigramOffset < 0) ? FormatSpec.FLAG_ATTRIBUTE_OFFSET_NEGATIVE : 0;
+                switch (BinaryDictInputOutput.getByteSize(bigramOffset)) {
+                case 1:
+                    bigramFlags |= FormatSpec.FLAG_ATTRIBUTE_ADDRESS_TYPE_ONEBYTE;
+                    break;
+                case 2:
+                    bigramFlags |= FormatSpec.FLAG_ATTRIBUTE_ADDRESS_TYPE_TWOBYTES;
+                    break;
+                case 3:
+                    bigramFlags |= FormatSpec.FLAG_ATTRIBUTE_ADDRESS_TYPE_THREEBYTES;
+                    break;
+                }
+                bigramFlags |= bigramFrequency & FormatSpec.FLAG_ATTRIBUTE_FREQUENCY;
+                destination.write((byte)bigramFlags);
+                size += writeVariableAddress(destination, Math.abs(bigramOffset));
+            }
+        }
+        return size;
+    }
+
+    @SuppressWarnings("unused")
+    private static void updateForwardLink(final FusionDictionaryBufferInterface buffer,
+            final int nodeOriginAddress, final int newNodeAddress,
+            final FormatOptions formatOptions) {
+        buffer.position(nodeOriginAddress);
+        int jumpCount = 0;
+        while (jumpCount++ < MAX_JUMPS) {
+            final int count = BinaryDictInputOutput.readCharGroupCount(buffer);
+            for (int i = 0; i < count; ++i) skipCharGroup(buffer, formatOptions);
+            final int forwardLinkAddress = buffer.readUnsignedInt24();
+            if (forwardLinkAddress == FormatSpec.NO_FORWARD_LINK_ADDRESS) {
+                buffer.position(buffer.position() - FormatSpec.FORWARD_LINK_ADDRESS_SIZE);
+                writeSInt24ToBuffer(buffer, newNodeAddress);
+                return;
+            }
+            buffer.position(forwardLinkAddress);
+        }
+        if (DBG && jumpCount >= MAX_JUMPS) {
+            throw new RuntimeException("too many jumps, probably a bug.");
+        }
+    }
+
+    /**
+     * Helper method to move a char group to the tail of the file.
+     */
+    private static int moveCharGroup(final OutputStream destination,
+            final FusionDictionaryBufferInterface buffer, final CharGroupInfo info,
+            final int nodeOriginAddress, final int oldGroupAddress,
+            final FormatOptions formatOptions) throws IOException {
+        updateParentAddress(buffer, oldGroupAddress, buffer.limit() + 1, formatOptions);
+        buffer.position(oldGroupAddress);
+        final int currentFlags = buffer.readUnsignedByte();
+        buffer.position(oldGroupAddress);
+        buffer.put((byte)(FormatSpec.FLAG_IS_MOVED | (currentFlags
+                & (~FormatSpec.MASK_MOVE_AND_DELETE_FLAG))));
+        int size = FormatSpec.GROUP_FLAGS_SIZE;
+        updateForwardLink(buffer, nodeOriginAddress, buffer.limit(), formatOptions);
+        size += writeNode(destination, new CharGroupInfo[] { info });
+        return size;
+    }
+
+    /**
+     * Compute the size of the char group.
+     */
+    private static int computeGroupSize(final CharGroupInfo info,
+            final FormatOptions formatOptions) {
+        int size = FormatSpec.GROUP_FLAGS_SIZE + FormatSpec.PARENT_ADDRESS_SIZE
+                + BinaryDictInputOutput.getGroupCharactersSize(info.mCharacters)
+                + BinaryDictInputOutput.getChildrenAddressSize(info.mFlags, formatOptions);
+        if ((info.mFlags & FormatSpec.FLAG_IS_TERMINAL) != 0) {
+            size += FormatSpec.GROUP_FREQUENCY_SIZE;
+        }
+        if (info.mShortcutTargets != null && !info.mShortcutTargets.isEmpty()) {
+            size += BinaryDictInputOutput.getShortcutListSize(info.mShortcutTargets);
+        }
+        if (info.mBigrams != null) {
+            for (final PendingAttribute attr : info.mBigrams) {
+                size += FormatSpec.GROUP_FLAGS_SIZE;
+                size += BinaryDictInputOutput.getByteSize(attr.mAddress);
+            }
+        }
+        return size;
+    }
+
+    /**
+     * Write a node to the stream.
+     *
+     * @param destination the stream to write.
+     * @param infos groups to be written.
+     * @return the size written, in bytes.
+     * @throws IOException
+     */
+    private static int writeNode(final OutputStream destination, final CharGroupInfo[] infos)
+            throws IOException {
+        int size = BinaryDictInputOutput.getGroupCountSize(infos.length);
+        switch (BinaryDictInputOutput.getGroupCountSize(infos.length)) {
+            case 1:
+                destination.write((byte)infos.length);
+                break;
+            case 2:
+                destination.write((byte)(infos.length >> 8));
+                destination.write((byte)(infos.length & 0xFF));
+                break;
+            default:
+                throw new RuntimeException("Invalid group count size.");
+        }
+        for (final CharGroupInfo info : infos) size += writeCharGroup(destination, info);
+        writeSInt24ToStream(destination, FormatSpec.NO_FORWARD_LINK_ADDRESS);
+        return size + FormatSpec.FORWARD_LINK_ADDRESS_SIZE;
+    }
+
+    /**
+     * Move a group that is referred to by oldGroupOrigin to the tail of the file.
+     * And set the children address to the byte after the group.
+     *
+     * @param nodeOrigin the address of the tail of the file.
+     * @param characters
+     * @param length
+     * @param flags
+     * @param frequency
+     * @param parentAddress
+     * @param shortcutTargets
+     * @param bigrams
+     * @param destination the stream representing the tail of the file.
+     * @param buffer the buffer representing the (constant-size) body of the file.
+     * @param oldNodeOrigin
+     * @param oldGroupOrigin
+     * @param formatOptions
+     * @return the size written, in bytes.
+     * @throws IOException
+     */
+    private static int moveGroup(final int nodeOrigin, final int[] characters, final int length,
+            final int flags, final int frequency, final int parentAddress,
+            final ArrayList<WeightedString> shortcutTargets,
+            final ArrayList<PendingAttribute> bigrams, final OutputStream destination,
+            final FusionDictionaryBufferInterface buffer, final int oldNodeOrigin,
+            final int oldGroupOrigin, final FormatOptions formatOptions) throws IOException {
+        int size = 0;
+        final int newGroupOrigin = nodeOrigin + 1;
+        final int[] writtenCharacters = Arrays.copyOfRange(characters, 0, length);
+        final CharGroupInfo tmpInfo = new CharGroupInfo(newGroupOrigin, -1 /* endAddress */,
+                flags, writtenCharacters, frequency, parentAddress, FormatSpec.NO_CHILDREN_ADDRESS,
+                shortcutTargets, bigrams);
+        size = computeGroupSize(tmpInfo, formatOptions);
+        final CharGroupInfo newInfo = new CharGroupInfo(newGroupOrigin, newGroupOrigin + size,
+                flags, writtenCharacters, frequency, parentAddress,
+                nodeOrigin + 1 + size + FormatSpec.FORWARD_LINK_ADDRESS_SIZE, shortcutTargets,
+                bigrams);
+        moveCharGroup(destination, buffer, newInfo, oldNodeOrigin, oldGroupOrigin, formatOptions);
+        return 1 + size + FormatSpec.FORWARD_LINK_ADDRESS_SIZE;
+    }
+
+    /**
+     * Insert a word into a binary dictionary.
+     *
+     * @param buffer
+     * @param destination
+     * @param word
+     * @param frequency
+     * @param bigramStrings
+     * @param shortcuts
+     * @throws IOException
+     * @throws UnsupportedFormatException
+     */
+    // TODO: Support batch insertion.
+    // TODO: Remove @UsedForTesting once UserHistoryDictionary is implemented by BinaryDictionary.
+    @UsedForTesting
+    public static void insertWord(final FusionDictionaryBufferInterface buffer,
+            final OutputStream destination, final String word, final int frequency,
+            final ArrayList<WeightedString> bigramStrings,
+            final ArrayList<WeightedString> shortcuts, final boolean isNotAWord,
+            final boolean isBlackListEntry)
+                    throws IOException, UnsupportedFormatException {
+        final ArrayList<PendingAttribute> bigrams = new ArrayList<PendingAttribute>();
+        if (bigramStrings != null) {
+            for (final WeightedString bigram : bigramStrings) {
+                int position = getTerminalPosition(buffer, bigram.mWord);
+                if (position == FormatSpec.NOT_VALID_WORD) {
+                    // TODO: figure out what is the correct thing to do here.
+                } else {
+                    bigrams.add(new PendingAttribute(bigram.mFrequency, position));
+                }
+            }
+        }
+
+        final boolean isTerminal = true;
+        final boolean hasBigrams = !bigrams.isEmpty();
+        final boolean hasShortcuts = shortcuts != null && !shortcuts.isEmpty();
+
+        // find the insert position of the word.
+        if (buffer.position() != 0) buffer.position(0);
+        final FileHeader header = BinaryDictInputOutput.readHeader(buffer);
+
+        int wordPos = 0, address = buffer.position(), nodeOriginAddress = buffer.position();
+        final int[] codePoints = FusionDictionary.getCodePoints(word);
+        final int wordLen = codePoints.length;
+
+        for (int depth = 0; depth < Constants.Dictionary.MAX_WORD_LENGTH; ++depth) {
+            if (wordPos >= wordLen) break;
+            nodeOriginAddress = buffer.position();
+            int nodeParentAddress = -1;
             final int charGroupCount = BinaryDictInputOutput.readCharGroupCount(buffer);
-            groupOffset += BinaryDictInputOutput.getGroupCountSize(charGroupCount);
+            boolean foundNextGroup = false;
 
             for (int i = 0; i < charGroupCount; ++i) {
-                final int charGroupPos = buffer.position();
+                address = buffer.position();
                 final CharGroupInfo currentInfo = BinaryDictInputOutput.readCharGroup(buffer,
                         buffer.position(), header.mFormatOptions);
-                boolean same = true;
-                for (int p = 0, j = word.offsetByCodePoints(0, wordPos);
-                        p < currentInfo.mCharacters.length;
-                        ++p, j = word.offsetByCodePoints(j, 1)) {
-                    if (wordPos + p >= wordLen
-                            || word.codePointAt(j) != currentInfo.mCharacters[p]) {
-                        same = false;
+                final boolean isMovedGroup = BinaryDictInputOutput.isMovedGroup(currentInfo.mFlags,
+                        header.mFormatOptions);
+                if (isMovedGroup) continue;
+                nodeParentAddress = (currentInfo.mParentAddress == FormatSpec.NO_PARENT_ADDRESS)
+                        ? FormatSpec.NO_PARENT_ADDRESS : currentInfo.mParentAddress + address;
+                boolean matched = true;
+                for (int p = 0; p < currentInfo.mCharacters.length; ++p) {
+                    if (wordPos + p >= wordLen) {
+                        /*
+                         * splitting
+                         * before
+                         *  abcd - ef
+                         *
+                         * insert "abc"
+                         *
+                         * after
+                         *  abc - d - ef
+                         */
+                        final int newNodeAddress = buffer.limit();
+                        final int flags = BinaryDictInputOutput.makeCharGroupFlags(p > 1,
+                                isTerminal, 0, hasShortcuts, hasBigrams, false /* isNotAWord */,
+                                false /* isBlackListEntry */, header.mFormatOptions);
+                        int written = moveGroup(newNodeAddress, currentInfo.mCharacters, p, flags,
+                                frequency, nodeParentAddress, shortcuts, bigrams, destination,
+                                buffer, nodeOriginAddress, address, header.mFormatOptions);
+
+                        final int[] characters2 = Arrays.copyOfRange(currentInfo.mCharacters, p,
+                                currentInfo.mCharacters.length);
+                        if (currentInfo.mChildrenAddress != FormatSpec.NO_CHILDREN_ADDRESS) {
+                            updateParentAddresses(buffer, currentInfo.mChildrenAddress,
+                                    newNodeAddress + written + 1, header.mFormatOptions);
+                        }
+                        final CharGroupInfo newInfo2 = new CharGroupInfo(
+                                newNodeAddress + written + 1, -1 /* endAddress */,
+                                currentInfo.mFlags, characters2, currentInfo.mFrequency,
+                                newNodeAddress + 1, currentInfo.mChildrenAddress,
+                                currentInfo.mShortcutTargets, currentInfo.mBigrams);
+                        writeNode(destination, new CharGroupInfo[] { newInfo2 });
+                        return;
+                    } else if (codePoints[wordPos + p] != currentInfo.mCharacters[p]) {
+                        if (p > 0) {
+                            /*
+                             * splitting
+                             * before
+                             *   ab - cd
+                             *
+                             * insert "ac"
+                             *
+                             * after
+                             *   a - b - cd
+                             *     |
+                             *     - c
+                             */
+
+                            final int newNodeAddress = buffer.limit();
+                            final int childrenAddress = currentInfo.mChildrenAddress;
+
+                            // move prefix
+                            final int prefixFlags = BinaryDictInputOutput.makeCharGroupFlags(p > 1,
+                                    false /* isTerminal */, 0 /* childrenAddressSize*/,
+                                    false /* hasShortcut */, false /* hasBigrams */,
+                                    false /* isNotAWord */, false /* isBlackListEntry */,
+                                    header.mFormatOptions);
+                            int written = moveGroup(newNodeAddress, currentInfo.mCharacters, p,
+                                    prefixFlags, -1 /* frequency */, nodeParentAddress, null, null,
+                                    destination, buffer, nodeOriginAddress, address,
+                                    header.mFormatOptions);
+
+                            final int[] suffixCharacters = Arrays.copyOfRange(
+                                    currentInfo.mCharacters, p, currentInfo.mCharacters.length);
+                            if (currentInfo.mChildrenAddress != FormatSpec.NO_CHILDREN_ADDRESS) {
+                                updateParentAddresses(buffer, currentInfo.mChildrenAddress,
+                                        newNodeAddress + written + 1, header.mFormatOptions);
+                            }
+                            final int suffixFlags = BinaryDictInputOutput.makeCharGroupFlags(
+                                    suffixCharacters.length > 1,
+                                    (currentInfo.mFlags & FormatSpec.FLAG_IS_TERMINAL) != 0,
+                                    0 /* childrenAddressSize */,
+                                    (currentInfo.mFlags & FormatSpec.FLAG_HAS_SHORTCUT_TARGETS)
+                                            != 0,
+                                    (currentInfo.mFlags & FormatSpec.FLAG_HAS_BIGRAMS) != 0,
+                                    isNotAWord, isBlackListEntry, header.mFormatOptions);
+                            final CharGroupInfo suffixInfo = new CharGroupInfo(
+                                    newNodeAddress + written + 1, -1 /* endAddress */, suffixFlags,
+                                    suffixCharacters, currentInfo.mFrequency, newNodeAddress + 1,
+                                    currentInfo.mChildrenAddress, currentInfo.mShortcutTargets,
+                                    currentInfo.mBigrams);
+                            written += computeGroupSize(suffixInfo, header.mFormatOptions) + 1;
+
+                            final int[] newCharacters = Arrays.copyOfRange(codePoints, wordPos + p,
+                                    codePoints.length);
+                            final int flags = BinaryDictInputOutput.makeCharGroupFlags(
+                                    newCharacters.length > 1, isTerminal,
+                                    0 /* childrenAddressSize */, hasShortcuts, hasBigrams,
+                                    isNotAWord, isBlackListEntry, header.mFormatOptions);
+                            final CharGroupInfo newInfo = new CharGroupInfo(
+                                    newNodeAddress + written, -1 /* endAddress */, flags,
+                                    newCharacters, frequency, newNodeAddress + 1,
+                                    FormatSpec.NO_CHILDREN_ADDRESS, shortcuts, bigrams);
+                            writeNode(destination, new CharGroupInfo[] { suffixInfo, newInfo });
+                            return;
+                        }
+                        matched = false;
                         break;
                     }
                 }
 
-                if (same) {
+                if (matched) {
                     if (wordPos + currentInfo.mCharacters.length == wordLen) {
-                        if (currentInfo.mFrequency == CharGroup.NOT_A_TERMINAL) {
-                            return FormatSpec.NOT_VALID_WORD;
-                        } else {
-                            return charGroupPos;
-                        }
+                        // the word exists in the dictionary.
+                        // only update group.
+                        final int newNodeAddress = buffer.limit();
+                        final boolean hasMultipleChars = currentInfo.mCharacters.length > 1;
+                        final int flags = BinaryDictInputOutput.makeCharGroupFlags(hasMultipleChars,
+                                isTerminal, 0 /* childrenAddressSize */, hasShortcuts, hasBigrams,
+                                isNotAWord, isBlackListEntry, header.mFormatOptions);
+                        final CharGroupInfo newInfo = new CharGroupInfo(newNodeAddress + 1,
+                                -1 /* endAddress */, flags, currentInfo.mCharacters, frequency,
+                                nodeParentAddress, currentInfo.mChildrenAddress, shortcuts,
+                                bigrams);
+                        moveCharGroup(destination, buffer, newInfo, nodeOriginAddress, address,
+                                header.mFormatOptions);
+                        return;
                     }
                     wordPos += currentInfo.mCharacters.length;
                     if (currentInfo.mChildrenAddress == FormatSpec.NO_CHILDREN_ADDRESS) {
-                        return FormatSpec.NOT_VALID_WORD;
+                        /*
+                         * found the prefix of the word.
+                         * make new node and link to the node from this group.
+                         *
+                         * before
+                         * ab - cd
+                         *
+                         * insert "abcde"
+                         *
+                         * after
+                         * ab - cd - e
+                         */
+                        final int newNodeAddress = buffer.limit();
+                        updateChildrenAddress(buffer, address, newNodeAddress,
+                                header.mFormatOptions);
+                        final int newGroupAddress = newNodeAddress + 1;
+                        final boolean hasMultipleChars = (wordLen - wordPos) > 1;
+                        final int flags = BinaryDictInputOutput.makeCharGroupFlags(hasMultipleChars,
+                                isTerminal, 0 /* childrenAddressSize */, hasShortcuts, hasBigrams,
+                                isNotAWord, isBlackListEntry, header.mFormatOptions);
+                        final int[] characters = Arrays.copyOfRange(codePoints, wordPos, wordLen);
+                        final CharGroupInfo newInfo = new CharGroupInfo(newGroupAddress, -1, flags,
+                                characters, frequency, address, FormatSpec.NO_CHILDREN_ADDRESS,
+                                shortcuts, bigrams);
+                        writeNode(destination, new CharGroupInfo[] { newInfo });
+                        return;
                     }
                     buffer.position(currentInfo.mChildrenAddress);
+                    foundNextGroup = true;
                     break;
                 }
-                groupOffset = currentInfo.mEndAddress;
+            }
 
-                // not found
-                if (i >= charGroupCount - 1) {
-                    return FormatSpec.NOT_VALID_WORD;
-                }
+            if (foundNextGroup) continue;
+
+            // reached the end of the array.
+            final int linkAddressPosition = buffer.position();
+            int nextLink = buffer.readUnsignedInt24();
+            if ((nextLink & MSB24) != 0) {
+                nextLink = -(nextLink & SINT24_MAX);
+            }
+            if (nextLink == FormatSpec.NO_FORWARD_LINK_ADDRESS) {
+                /*
+                 * expand this node.
+                 *
+                 * before
+                 * ab - cd
+                 *
+                 * insert "abef"
+                 *
+                 * after
+                 * ab - cd
+                 *    |
+                 *    - ef
+                 */
+
+                // change the forward link address.
+                final int newNodeAddress = buffer.limit();
+                buffer.position(linkAddressPosition);
+                writeSInt24ToBuffer(buffer, newNodeAddress);
+
+                final int[] characters = Arrays.copyOfRange(codePoints, wordPos, wordLen);
+                final int flags = BinaryDictInputOutput.makeCharGroupFlags(characters.length > 1,
+                        isTerminal, 0 /* childrenAddressSize */, hasShortcuts, hasBigrams,
+                        isNotAWord, isBlackListEntry, header.mFormatOptions);
+                final CharGroupInfo newInfo = new CharGroupInfo(newNodeAddress + 1,
+                        -1 /* endAddress */, flags, characters, frequency, nodeParentAddress,
+                        FormatSpec.NO_CHILDREN_ADDRESS, shortcuts, bigrams);
+                writeNode(destination, new CharGroupInfo[]{ newInfo });
+                return;
+            } else {
+                depth--;
+                buffer.position(nextLink);
             }
         }
-        return FormatSpec.NOT_VALID_WORD;
+    }
+
+    /**
+     * Find a word from the buffer.
+     *
+     * @param buffer the buffer representing the body of the dictionary file.
+     * @param word the word searched
+     * @return the found group
+     * @throws IOException
+     * @throws UnsupportedFormatException
+     */
+    @UsedForTesting
+    public static CharGroupInfo findWordFromBuffer(final FusionDictionaryBufferInterface buffer,
+            final String word) throws IOException, UnsupportedFormatException {
+        int position = getTerminalPosition(buffer, word);
+        if (position != FormatSpec.NOT_VALID_WORD) {
+            buffer.position(0);
+            final FileHeader header = BinaryDictInputOutput.readHeader(buffer);
+            buffer.position(position);
+            return BinaryDictInputOutput.readCharGroup(buffer, position, header.mFormatOptions);
+        }
+        return null;
     }
 }
diff --git a/java/src/com/android/inputmethod/latin/makedict/BinaryDictInputOutput.java b/java/src/com/android/inputmethod/latin/makedict/BinaryDictInputOutput.java
index 1d3e94bb7..d1a3c7b0a 100644
--- a/java/src/com/android/inputmethod/latin/makedict/BinaryDictInputOutput.java
+++ b/java/src/com/android/inputmethod/latin/makedict/BinaryDictInputOutput.java
@@ -16,6 +16,7 @@
 
 package com.android.inputmethod.latin.makedict;
 
+import com.android.inputmethod.annotations.UsedForTesting;
 import com.android.inputmethod.latin.makedict.FormatSpec.FileHeader;
 import com.android.inputmethod.latin.makedict.FormatSpec.FormatOptions;
 import com.android.inputmethod.latin.makedict.FusionDictionary.CharGroup;
@@ -36,7 +37,6 @@ import java.util.Arrays;
 import java.util.HashMap;
 import java.util.Iterator;
 import java.util.Map;
-import java.util.Stack;
 import java.util.TreeMap;
 
 /**
@@ -44,7 +44,7 @@ import java.util.TreeMap;
  *
  * All the methods in this class are static.
  */
-public class BinaryDictInputOutput {
+public final class BinaryDictInputOutput {
 
     private static final boolean DBG = MakedictLog.DBG;
 
@@ -54,6 +54,7 @@ public class BinaryDictInputOutput {
     // If the number of passes exceeds this number, makedict bails with an exception on
     // suspicion that a bug might be causing an infinite loop.
     private static final int MAX_PASSES = 24;
+    private static final int MAX_JUMPS = 12;
 
     public interface FusionDictionaryBufferInterface {
         public int readUnsignedByte();
@@ -64,6 +65,7 @@ public class BinaryDictInputOutput {
         public void position(int newPosition);
         public void put(final byte b);
         public int limit();
+        public int capacity();
     }
 
     public static final class ByteBufferWrapper implements FusionDictionaryBufferInterface {
@@ -75,12 +77,12 @@ public class BinaryDictInputOutput {
 
         @Override
         public int readUnsignedByte() {
-            return ((int)mBuffer.get()) & 0xFF;
+            return mBuffer.get() & 0xFF;
         }
 
         @Override
         public int readUnsignedShort() {
-            return ((int)mBuffer.getShort()) & 0xFFFF;
+            return mBuffer.getShort() & 0xFFFF;
         }
 
         @Override
@@ -113,13 +115,17 @@ public class BinaryDictInputOutput {
         public int limit() {
             return mBuffer.limit();
         }
+
+        @Override
+        public int capacity() {
+            return mBuffer.capacity();
+        }
     }
 
     /**
      * A class grouping utility function for our specific character encoding.
      */
-    private static class CharEncoding {
-
+    static final class CharEncoding {
         private static final int MINIMAL_ONE_BYTE_CHARACTER_VALUE = 0x20;
         private static final int MAXIMAL_ONE_BYTE_CHARACTER_VALUE = 0xFF;
 
@@ -148,7 +154,7 @@ public class BinaryDictInputOutput {
          * @param character the character code.
          * @return the size in binary encoded-form, either 1 or 3 bytes.
          */
-        private static int getCharSize(final int character) {
+        static int getCharSize(final int character) {
             // See char encoding in FusionDictionary.java
             if (fitsOnOneByte(character)) return 1;
             if (FormatSpec.INVALID_CHARACTER == character) return 1;
@@ -257,7 +263,7 @@ public class BinaryDictInputOutput {
          * @param buffer the buffer, positioned over an encoded character.
          * @return the character code.
          */
-        private static int readChar(final FusionDictionaryBufferInterface buffer) {
+        static int readChar(final FusionDictionaryBufferInterface buffer) {
             int character = buffer.readUnsignedByte();
             if (!fitsOnOneByte(character)) {
                 if (FormatSpec.GROUP_CHARACTERS_TERMINATOR == character) {
@@ -271,6 +277,21 @@ public class BinaryDictInputOutput {
     }
 
     /**
+     * Compute the binary size of the character array.
+     *
+     * If only one character, this is the size of this character. If many, it's the sum of their
+     * sizes + 1 byte for the terminator.
+     *
+     * @param characters the character array
+     * @return the size of the char array, including the terminator if any
+     */
+    static int getGroupCharactersSize(final int[] characters) {
+        int size = CharEncoding.getCharArraySize(characters);
+        if (characters.length > 1) size += FormatSpec.GROUP_TERMINATOR_SIZE;
+        return size;
+    }
+
+    /**
      * Compute the binary size of the character array in a group
      *
      * If only one character, this is the size of this character. If many, it's the sum of their
@@ -280,9 +301,7 @@ public class BinaryDictInputOutput {
      * @return the size of the char array, including the terminator if any
      */
     private static int getGroupCharactersSize(final CharGroup group) {
-        int size = CharEncoding.getCharArraySize(group.mChars);
-        if (group.hasSeveralChars()) size += FormatSpec.GROUP_TERMINATOR_SIZE;
-        return size;
+        return getGroupCharactersSize(group.mChars);
     }
 
     /**
@@ -332,7 +351,7 @@ public class BinaryDictInputOutput {
      * This is known in advance and does not change according to position in the file
      * like address lists do.
      */
-    private static int getShortcutListSize(final ArrayList<WeightedString> shortcutList) {
+    static int getShortcutListSize(final ArrayList<WeightedString> shortcutList) {
         if (null == shortcutList) return 0;
         int size = FormatSpec.GROUP_SHORTCUT_LIST_SIZE_SIZE;
         for (final WeightedString shortcut : shortcutList) {
@@ -376,7 +395,7 @@ public class BinaryDictInputOutput {
             g.mCachedSize = groupSize;
             size += groupSize;
         }
-        if (options.mHasLinkedListNode) {
+        if (options.mSupportsDynamicUpdate) {
             size += FormatSpec.FORWARD_LINK_ADDRESS_SIZE;
         }
         node.mCachedSize = size;
@@ -390,11 +409,27 @@ public class BinaryDictInputOutput {
     }
 
     /**
-     * Helper method to check whether the CharGroup has a parent address.
+     * Helper method to check whether the group is moved.
      */
-    private static boolean hasParentAddress(final FormatOptions options) {
-        return options.mVersion >= FormatSpec.FIRST_VERSION_WITH_PARENT_ADDRESS
-                && options.mHasParentAddress;
+    public static boolean isMovedGroup(final int flags, final FormatOptions options) {
+        return options.mSupportsDynamicUpdate
+                && ((flags & FormatSpec.MASK_GROUP_ADDRESS_TYPE) == FormatSpec.FLAG_IS_MOVED);
+    }
+
+    /**
+     * Helper method to check whether the group is deleted.
+     */
+    public static boolean isDeletedGroup(final int flags, final FormatOptions formatOptions) {
+        return formatOptions.mSupportsDynamicUpdate
+                && ((flags & FormatSpec.MASK_GROUP_ADDRESS_TYPE) == FormatSpec.FLAG_IS_DELETED);
+    }
+
+    /**
+     * Helper method to check whether the dictionary can be updated dynamically.
+     */
+    public static boolean supportsDynamicUpdate(final FormatOptions options) {
+        return options.mVersion >= FormatSpec.FIRST_VERSION_WITH_DYNAMIC_UPDATE
+                && options.mSupportsDynamicUpdate;
     }
 
     /**
@@ -404,7 +439,7 @@ public class BinaryDictInputOutput {
      * @param options file format options.
      */
     private static int getGroupHeaderSize(final CharGroup group, final FormatOptions options) {
-        if (hasParentAddress(options)) {
+        if (supportsDynamicUpdate(options)) {
             return FormatSpec.GROUP_FLAGS_SIZE + FormatSpec.PARENT_ADDRESS_SIZE
                     + getGroupCharactersSize(group);
         } else {
@@ -412,6 +447,10 @@ public class BinaryDictInputOutput {
         }
     }
 
+    private static final int UINT8_MAX = 0xFF;
+    private static final int UINT16_MAX = 0xFFFF;
+    private static final int UINT24_MAX = 0xFFFFFF;
+
     /**
      * Compute the size, in bytes, that an address will occupy.
      *
@@ -422,18 +461,23 @@ public class BinaryDictInputOutput {
      * @param address the address
      * @return the byte size.
      */
-    private static int getByteSize(final int address) {
-        assert(address < 0x1000000);
+    static int getByteSize(final int address) {
+        assert(address <= UINT24_MAX);
         if (!hasChildrenAddress(address)) {
             return 0;
-        } else if (Math.abs(address) < 0x100) {
+        } else if (Math.abs(address) <= UINT8_MAX) {
             return 1;
-        } else if (Math.abs(address) < 0x10000) {
+        } else if (Math.abs(address) <= UINT16_MAX) {
             return 2;
         } else {
             return 3;
         }
     }
+
+    private static final int SINT24_MAX = 0x7FFFFF;
+    private static final int MSB8 = 0x80;
+    private static final int MSB24 = 0x800000;
+
     // End utility methods.
 
     // This method is responsible for finding a nice ordering of the nodes that favors run-time
@@ -509,13 +553,19 @@ public class BinaryDictInputOutput {
             }
             int groupSize = getGroupHeaderSize(group, formatOptions);
             if (group.isTerminal()) groupSize += FormatSpec.GROUP_FREQUENCY_SIZE;
-            if (null != group.mChildren) {
+            if (null == group.mChildren && formatOptions.mSupportsDynamicUpdate) {
+                groupSize += FormatSpec.SIGNED_CHILDREN_ADDRESS_SIZE;
+            } else if (null != group.mChildren) {
                 final int offsetBasePoint = groupSize + node.mCachedAddress + size;
                 final int offset = group.mChildren.mCachedAddress - offsetBasePoint;
                 // assign my address to children's parent address
                 group.mChildren.mCachedParentAddress = group.mCachedAddress
                         - group.mChildren.mCachedAddress;
-                groupSize += getByteSize(offset);
+                if (formatOptions.mSupportsDynamicUpdate) {
+                    groupSize += FormatSpec.SIGNED_CHILDREN_ADDRESS_SIZE;
+                } else {
+                    groupSize += getByteSize(offset);
+                }
             }
             groupSize += getShortcutListSize(group.mShortcutTargets);
             if (null != group.mBigrams) {
@@ -530,7 +580,7 @@ public class BinaryDictInputOutput {
             group.mCachedSize = groupSize;
             size += groupSize;
         }
-        if (formatOptions.mHasLinkedListNode) {
+        if (formatOptions.mSupportsDynamicUpdate) {
             size += FormatSpec.FORWARD_LINK_ADDRESS_SIZE;
         }
         if (node.mCachedSize != size) {
@@ -559,7 +609,8 @@ public class BinaryDictInputOutput {
                 groupOffset += g.mCachedSize;
             }
             final int nodeSize = groupCountSize + groupOffset
-                    + (formatOptions.mHasLinkedListNode ? FormatSpec.FORWARD_LINK_ADDRESS_SIZE : 0);
+                    + (formatOptions.mSupportsDynamicUpdate
+                            ? FormatSpec.FORWARD_LINK_ADDRESS_SIZE : 0);
             if (nodeSize != n.mCachedSize) {
                 throw new RuntimeException("Bug : Stored and computed node size differ");
             }
@@ -668,49 +719,81 @@ public class BinaryDictInputOutput {
         }
     }
 
-    private static byte makeCharGroupFlags(final CharGroup group, final int groupAddress,
-            final int childrenOffset) {
-        byte flags = 0;
-        if (group.mChars.length > 1) flags |= FormatSpec.FLAG_HAS_MULTIPLE_CHARS;
-        if (group.mFrequency >= 0) {
-            flags |= FormatSpec.FLAG_IS_TERMINAL;
-        }
-        if (null != group.mChildren) {
-            switch (getByteSize(childrenOffset)) {
-             case 1:
-                 flags |= FormatSpec.FLAG_GROUP_ADDRESS_TYPE_ONEBYTE;
-                 break;
-             case 2:
-                 flags |= FormatSpec.FLAG_GROUP_ADDRESS_TYPE_TWOBYTES;
-                 break;
-             case 3:
-                 flags |= FormatSpec.FLAG_GROUP_ADDRESS_TYPE_THREEBYTES;
-                 break;
-             default:
-                 throw new RuntimeException("Node with a strange address");
-             }
-        }
-        if (null != group.mShortcutTargets) {
-            if (DBG && 0 == group.mShortcutTargets.size()) {
-                throw new RuntimeException("0-sized shortcut list must be null");
-            }
-            flags |= FormatSpec.FLAG_HAS_SHORTCUT_TARGETS;
+    /**
+     * Helper method to write a variable-size signed address to a file.
+     *
+     * @param buffer the buffer to write to.
+     * @param index the index in the buffer to write the address to.
+     * @param address the address to write.
+     * @return the size in bytes the address actually took.
+     */
+    private static int writeVariableSignedAddress(final byte[] buffer, int index,
+            final int address) {
+        if (!hasChildrenAddress(address)) {
+            buffer[index] = buffer[index + 1] = buffer[index + 2] = 0;
+        } else {
+            final int absAddress = Math.abs(address);
+            buffer[index++] = (byte)((address < 0 ? MSB8 : 0) | (0xFF & (absAddress >> 16)));
+            buffer[index++] = (byte)(0xFF & (absAddress >> 8));
+            buffer[index++] = (byte)(0xFF & absAddress);
         }
-        if (null != group.mBigrams) {
-            if (DBG && 0 == group.mBigrams.size()) {
-                throw new RuntimeException("0-sized bigram list must be null");
+        return 3;
+    }
+
+    /**
+     * Makes the flag value for a char group.
+     *
+     * @param hasMultipleChars whether the group has multiple chars.
+     * @param isTerminal whether the group is terminal.
+     * @param childrenAddressSize the size of a children address.
+     * @param hasShortcuts whether the group has shortcuts.
+     * @param hasBigrams whether the group has bigrams.
+     * @param isNotAWord whether the group is not a word.
+     * @param isBlackListEntry whether the group is a blacklist entry.
+     * @param formatOptions file format options.
+     * @return the flags
+     */
+    static int makeCharGroupFlags(final boolean hasMultipleChars, final boolean isTerminal,
+            final int childrenAddressSize, final boolean hasShortcuts, final boolean hasBigrams,
+            final boolean isNotAWord, final boolean isBlackListEntry,
+            final FormatOptions formatOptions) {
+        byte flags = 0;
+        if (hasMultipleChars) flags |= FormatSpec.FLAG_HAS_MULTIPLE_CHARS;
+        if (isTerminal) flags |= FormatSpec.FLAG_IS_TERMINAL;
+        if (formatOptions.mSupportsDynamicUpdate) {
+            flags |= FormatSpec.FLAG_IS_NOT_MOVED;
+        } else if (true) {
+            switch (childrenAddressSize) {
+                case 1:
+                    flags |= FormatSpec.FLAG_GROUP_ADDRESS_TYPE_ONEBYTE;
+                    break;
+                case 2:
+                    flags |= FormatSpec.FLAG_GROUP_ADDRESS_TYPE_TWOBYTES;
+                    break;
+                case 3:
+                    flags |= FormatSpec.FLAG_GROUP_ADDRESS_TYPE_THREEBYTES;
+                    break;
+                case 0:
+                    flags |= FormatSpec.FLAG_GROUP_ADDRESS_TYPE_NOADDRESS;
+                    break;
+                default:
+                    throw new RuntimeException("Node with a strange address");
             }
-            flags |= FormatSpec.FLAG_HAS_BIGRAMS;
-        }
-        if (group.mIsNotAWord) {
-            flags |= FormatSpec.FLAG_IS_NOT_A_WORD;
-        }
-        if (group.mIsBlacklistEntry) {
-            flags |= FormatSpec.FLAG_IS_BLACKLISTED;
         }
+        if (hasShortcuts) flags |= FormatSpec.FLAG_HAS_SHORTCUT_TARGETS;
+        if (hasBigrams) flags |= FormatSpec.FLAG_HAS_BIGRAMS;
+        if (isNotAWord) flags |= FormatSpec.FLAG_IS_NOT_A_WORD;
+        if (isBlackListEntry) flags |= FormatSpec.FLAG_IS_BLACKLISTED;
         return flags;
     }
 
+    private static byte makeCharGroupFlags(final CharGroup group, final int groupAddress,
+            final int childrenOffset, final FormatOptions formatOptions) {
+        return (byte) makeCharGroupFlags(group.mChars.length > 1, group.mFrequency >= 0,
+                getByteSize(childrenOffset), group.mShortcutTargets != null, group.mBigrams != null,
+                group.mIsNotAWord, group.mIsBlacklistEntry, formatOptions);
+    }
+
     /**
      * Makes the flag value for a bigram.
      *
@@ -792,8 +875,7 @@ public class BinaryDictInputOutput {
         return (options.mFrenchLigatureProcessing ? FormatSpec.FRENCH_LIGATURE_PROCESSING_FLAG : 0)
                 + (options.mGermanUmlautProcessing ? FormatSpec.GERMAN_UMLAUT_PROCESSING_FLAG : 0)
                 + (hasBigrams ? FormatSpec.CONTAINS_BIGRAMS_FLAG : 0)
-                + (formatOptions.mHasParentAddress ? FormatSpec.HAS_PARENT_ADDRESS : 0)
-                + (formatOptions.mHasLinkedListNode ? FormatSpec.HAS_LINKEDLIST_NODE : 0);
+                + (formatOptions.mSupportsDynamicUpdate ? FormatSpec.SUPPORTS_DYNAMIC_UPDATE : 0);
     }
 
     /**
@@ -803,11 +885,30 @@ public class BinaryDictInputOutput {
      * @param frequency the frequency of the attribute, 0..15
      * @return the flags
      */
-    private static final int makeShortcutFlags(final boolean more, final int frequency) {
+    static final int makeShortcutFlags(final boolean more, final int frequency) {
         return (more ? FormatSpec.FLAG_ATTRIBUTE_HAS_NEXT : 0)
                 + (frequency & FormatSpec.FLAG_ATTRIBUTE_FREQUENCY);
     }
 
+    private static final int writeParentAddress(final byte[] buffer, final int index,
+            final int address, final FormatOptions formatOptions) {
+        if (supportsDynamicUpdate(formatOptions)) {
+            if (address == FormatSpec.NO_PARENT_ADDRESS) {
+                buffer[index] = buffer[index + 1] = buffer[index + 2] = 0;
+            } else {
+                final int absAddress = Math.abs(address);
+                assert(absAddress <= SINT24_MAX);
+                buffer[index] = (byte)((address < 0 ? MSB8 : 0)
+                        | ((absAddress >> 16) & 0xFF));
+                buffer[index + 1] = (byte)((absAddress >> 8) & 0xFF);
+                buffer[index + 2] = (byte)(absAddress & 0xFF);
+            }
+            return index + 3;
+        } else {
+            return index;
+        }
+    }
+
     /**
      * Write a node to memory. The node is expected to have its final position cached.
      *
@@ -822,6 +923,7 @@ public class BinaryDictInputOutput {
      */
     private static int writePlacedNode(final FusionDictionary dict, byte[] buffer,
             final Node node, final FormatOptions formatOptions) {
+        // TODO: Make the code in common with BinaryDictIOUtils#writeCharGroup
         int index = node.mCachedAddress;
 
         final int groupCount = node.mData.size();
@@ -854,22 +956,15 @@ public class BinaryDictInputOutput {
             final int childrenOffset = null == group.mChildren
                     ? FormatSpec.NO_CHILDREN_ADDRESS
                             : group.mChildren.mCachedAddress - groupAddress;
-            byte flags = makeCharGroupFlags(group, groupAddress, childrenOffset);
+            byte flags = makeCharGroupFlags(group, groupAddress, childrenOffset, formatOptions);
             buffer[index++] = flags;
 
-            if (hasParentAddress(formatOptions)) {
-                if (parentAddress == FormatSpec.NO_PARENT_ADDRESS) {
-                    // this node is the root node.
-                    buffer[index] = buffer[index + 1] = buffer[index + 2] = 0;
-                } else {
-                    // write parent address. (version 3)
-                    final int actualParentAddress = Math.abs(parentAddress
-                            + (node.mCachedAddress - group.mCachedAddress));
-                    buffer[index] = (byte)((actualParentAddress >> 16) & 0xFF);
-                    buffer[index + 1] = (byte)((actualParentAddress >> 8) & 0xFF);
-                    buffer[index + 2] = (byte)(actualParentAddress & 0xFF);
-                }
-                index += 3;
+            if (parentAddress == FormatSpec.NO_PARENT_ADDRESS) {
+                index = writeParentAddress(buffer, index, parentAddress, formatOptions);
+            } else {
+                index = writeParentAddress(buffer, index,
+                        parentAddress + (node.mCachedAddress - group.mCachedAddress),
+                        formatOptions);
             }
 
             index = CharEncoding.writeCharArray(group.mChars, buffer, index);
@@ -879,7 +974,13 @@ public class BinaryDictInputOutput {
             if (group.mFrequency >= 0) {
                 buffer[index++] = (byte) group.mFrequency;
             }
-            final int shift = writeVariableAddress(buffer, index, childrenOffset);
+
+            final int shift;
+            if (formatOptions.mSupportsDynamicUpdate) {
+                shift = writeVariableSignedAddress(buffer, index, childrenOffset);
+            } else {
+                shift = writeVariableAddress(buffer, index, childrenOffset);
+            }
             index += shift;
             groupAddress += shift;
 
@@ -927,7 +1028,7 @@ public class BinaryDictInputOutput {
             }
 
         }
-        if (formatOptions.mHasLinkedListNode) {
+        if (formatOptions.mSupportsDynamicUpdate) {
             buffer[index] = buffer[index + 1] = buffer[index + 2]
                     = FormatSpec.NO_FORWARD_LINK_ADDRESS;
             index += FormatSpec.FORWARD_LINK_ADDRESS_SIZE;
@@ -1104,6 +1205,58 @@ public class BinaryDictInputOutput {
     // Input methods: Read a binary dictionary to memory.
     // readDictionaryBinary is the public entry point for them.
 
+    static int getChildrenAddressSize(final int optionFlags,
+            final FormatOptions formatOptions) {
+        if (formatOptions.mSupportsDynamicUpdate) return FormatSpec.SIGNED_CHILDREN_ADDRESS_SIZE;
+        switch (optionFlags & FormatSpec.MASK_GROUP_ADDRESS_TYPE) {
+            case FormatSpec.FLAG_GROUP_ADDRESS_TYPE_ONEBYTE:
+                return 1;
+            case FormatSpec.FLAG_GROUP_ADDRESS_TYPE_TWOBYTES:
+                return 2;
+            case FormatSpec.FLAG_GROUP_ADDRESS_TYPE_THREEBYTES:
+                return 3;
+            case FormatSpec.FLAG_GROUP_ADDRESS_TYPE_NOADDRESS:
+            default:
+                return 0;
+        }
+    }
+
+    static int readChildrenAddress(final FusionDictionaryBufferInterface buffer,
+            final int optionFlags, final FormatOptions options) {
+        if (options.mSupportsDynamicUpdate) {
+            final int address = buffer.readUnsignedInt24();
+            if (address == 0) return FormatSpec.NO_CHILDREN_ADDRESS;
+            if ((address & MSB24) != 0) {
+                return -(address & SINT24_MAX);
+            } else {
+                return address;
+            }
+        }
+        int address;
+        switch (optionFlags & FormatSpec.MASK_GROUP_ADDRESS_TYPE) {
+            case FormatSpec.FLAG_GROUP_ADDRESS_TYPE_ONEBYTE:
+                return buffer.readUnsignedByte();
+            case FormatSpec.FLAG_GROUP_ADDRESS_TYPE_TWOBYTES:
+                return buffer.readUnsignedShort();
+            case FormatSpec.FLAG_GROUP_ADDRESS_TYPE_THREEBYTES:
+                return buffer.readUnsignedInt24();
+            case FormatSpec.FLAG_GROUP_ADDRESS_TYPE_NOADDRESS:
+            default:
+                return FormatSpec.NO_CHILDREN_ADDRESS;
+        }
+    }
+
+    static int readParentAddress(final FusionDictionaryBufferInterface buffer,
+            final FormatOptions formatOptions) {
+        if (supportsDynamicUpdate(formatOptions)) {
+            final int parentAddress = buffer.readUnsignedInt24();
+            final int sign = ((parentAddress & MSB24) != 0) ? -1 : 1;
+            return sign * (parentAddress & SINT24_MAX);
+        } else {
+            return FormatSpec.NO_PARENT_ADDRESS;
+        }
+    }
+
     private static final int[] CHARACTER_BUFFER = new int[FormatSpec.MAX_WORD_LENGTH];
     public static CharGroupInfo readCharGroup(final FusionDictionaryBufferInterface buffer,
             final int originalGroupAddress, final FormatOptions options) {
@@ -1111,13 +1264,9 @@ public class BinaryDictInputOutput {
         final int flags = buffer.readUnsignedByte();
         ++addressPointer;
 
-        final int parentAddress;
-        if (hasParentAddress(options)) {
-            // read the parent address. (version 3)
-            parentAddress = -buffer.readUnsignedInt24();
+        final int parentAddress = readParentAddress(buffer, options);
+        if (supportsDynamicUpdate(options)) {
             addressPointer += 3;
-        } else {
-            parentAddress = FormatSpec.NO_PARENT_ADDRESS;
         }
 
         final int characters[];
@@ -1146,25 +1295,11 @@ public class BinaryDictInputOutput {
         } else {
             frequency = CharGroup.NOT_A_TERMINAL;
         }
-        int childrenAddress = addressPointer;
-        switch (flags & FormatSpec.MASK_GROUP_ADDRESS_TYPE) {
-        case FormatSpec.FLAG_GROUP_ADDRESS_TYPE_ONEBYTE:
-            childrenAddress += buffer.readUnsignedByte();
-            addressPointer += 1;
-            break;
-        case FormatSpec.FLAG_GROUP_ADDRESS_TYPE_TWOBYTES:
-            childrenAddress += buffer.readUnsignedShort();
-            addressPointer += 2;
-            break;
-        case FormatSpec.FLAG_GROUP_ADDRESS_TYPE_THREEBYTES:
-            childrenAddress += buffer.readUnsignedInt24();
-            addressPointer += 3;
-            break;
-        case FormatSpec.FLAG_GROUP_ADDRESS_TYPE_NOADDRESS:
-        default:
-            childrenAddress = FormatSpec.NO_CHILDREN_ADDRESS;
-            break;
+        int childrenAddress = readChildrenAddress(buffer, flags, options);
+        if (childrenAddress != FormatSpec.NO_CHILDREN_ADDRESS) {
+            childrenAddress += addressPointer;
         }
+        addressPointer += getChildrenAddressSize(flags, options);
         ArrayList<WeightedString> shortcutTargets = null;
         if (0 != (flags & FormatSpec.FLAG_HAS_SHORTCUT_TARGETS)) {
             final int pointerBefore = buffer.position();
@@ -1182,7 +1317,8 @@ public class BinaryDictInputOutput {
         ArrayList<PendingAttribute> bigrams = null;
         if (0 != (flags & FormatSpec.FLAG_HAS_BIGRAMS)) {
             bigrams = new ArrayList<PendingAttribute>();
-            while (true) {
+            int bigramCount = 0;
+            while (bigramCount++ < FormatSpec.MAX_BIGRAMS_IN_A_GROUP) {
                 final int bigramFlags = buffer.readUnsignedByte();
                 ++addressPointer;
                 final int sign = 0 == (bigramFlags & FormatSpec.FLAG_ATTRIBUTE_OFFSET_NEGATIVE)
@@ -1210,6 +1346,9 @@ public class BinaryDictInputOutput {
                         bigramAddress));
                 if (0 == (bigramFlags & FormatSpec.FLAG_ATTRIBUTE_HAS_NEXT)) break;
             }
+            if (bigramCount >= FormatSpec.MAX_BIGRAMS_IN_A_GROUP) {
+                MakedictLog.d("too many bigrams in a group.");
+            }
         }
         return new CharGroupInfo(originalGroupAddress, addressPointer, flags, characters, frequency,
                 parentAddress, childrenAddress, shortcutTargets, bigrams);
@@ -1232,7 +1371,8 @@ public class BinaryDictInputOutput {
     // of this method. Since it performs direct, unbuffered random access to the file and
     // may be called hundreds of thousands of times, the resulting performance is not
     // reasonable without some kind of cache. Thus:
-    private static TreeMap<Integer, String> wordCache = new TreeMap<Integer, String>();
+    private static TreeMap<Integer, WeightedString> wordCache =
+            new TreeMap<Integer, WeightedString>();
     /**
      * Finds, as a string, the word at the address passed as an argument.
      *
@@ -1240,18 +1380,19 @@ public class BinaryDictInputOutput {
      * @param headerSize the size of the header.
      * @param address the address to seek.
      * @param formatOptions file format options.
-     * @return the word, as a string.
+     * @return the word with its frequency, as a weighted string.
      */
-    /* packages for tests */ static String getWordAtAddress(
+    /* package for tests */ static WeightedString getWordAtAddress(
             final FusionDictionaryBufferInterface buffer, final int headerSize, final int address,
             final FormatOptions formatOptions) {
-        final String cachedString = wordCache.get(address);
+        final WeightedString cachedString = wordCache.get(address);
         if (null != cachedString) return cachedString;
 
-        final String result;
+        final WeightedString result;
         final int originalPointer = buffer.position();
+        buffer.position(address);
 
-        if (hasParentAddress(formatOptions)) {
+        if (supportsDynamicUpdate(formatOptions)) {
             result = getWordAtAddressWithParentAddress(buffer, headerSize, address, formatOptions);
         } else {
             result = getWordAtAddressWithoutParentAddress(buffer, headerSize, address,
@@ -1263,38 +1404,53 @@ public class BinaryDictInputOutput {
         return result;
     }
 
+    // TODO: static!? This will behave erratically when used in multi-threaded code.
+    // We need to fix this
     private static int[] sGetWordBuffer = new int[FormatSpec.MAX_WORD_LENGTH];
-    private static String getWordAtAddressWithParentAddress(
+    private static WeightedString getWordAtAddressWithParentAddress(
             final FusionDictionaryBufferInterface buffer, final int headerSize, final int address,
             final FormatOptions options) {
         final StringBuilder builder = new StringBuilder();
 
         int currentAddress = address;
         int index = FormatSpec.MAX_WORD_LENGTH - 1;
+        int frequency = Integer.MIN_VALUE;
         // the length of the path from the root to the leaf is limited by MAX_WORD_LENGTH
         for (int count = 0; count < FormatSpec.MAX_WORD_LENGTH; ++count) {
-            buffer.position(currentAddress + headerSize);
-            final CharGroupInfo currentInfo = readCharGroup(buffer, currentAddress, options);
+            CharGroupInfo currentInfo;
+            int loopCounter = 0;
+            do {
+                buffer.position(currentAddress + headerSize);
+                currentInfo = readCharGroup(buffer, currentAddress, options);
+                if (isMovedGroup(currentInfo.mFlags, options)) {
+                    currentAddress = currentInfo.mParentAddress + currentInfo.mOriginalAddress;
+                }
+                if (DBG && loopCounter++ > MAX_JUMPS) {
+                    MakedictLog.d("Too many jumps - probably a bug");
+                }
+            } while (isMovedGroup(currentInfo.mFlags, options));
+            if (Integer.MIN_VALUE == frequency) frequency = currentInfo.mFrequency;
             for (int i = 0; i < currentInfo.mCharacters.length; ++i) {
                 sGetWordBuffer[index--] =
                         currentInfo.mCharacters[currentInfo.mCharacters.length - i - 1];
             }
-
             if (currentInfo.mParentAddress == FormatSpec.NO_PARENT_ADDRESS) break;
             currentAddress = currentInfo.mParentAddress + currentInfo.mOriginalAddress;
         }
 
-        return new String(sGetWordBuffer, index + 1, FormatSpec.MAX_WORD_LENGTH - index - 1);
+        return new WeightedString(
+                new String(sGetWordBuffer, index + 1, FormatSpec.MAX_WORD_LENGTH - index - 1),
+                        frequency);
     }
 
-    private static String getWordAtAddressWithoutParentAddress(
+    private static WeightedString getWordAtAddressWithoutParentAddress(
             final FusionDictionaryBufferInterface buffer, final int headerSize, final int address,
             final FormatOptions options) {
         buffer.position(headerSize);
         final int count = readCharGroupCount(buffer);
         int groupOffset = getGroupCountSize(count);
         final StringBuilder builder = new StringBuilder();
-        String result = null;
+        WeightedString result = null;
 
         CharGroupInfo last = null;
         for (int i = count - 1; i >= 0; --i) {
@@ -1302,7 +1458,7 @@ public class BinaryDictInputOutput {
             groupOffset = info.mEndAddress;
             if (info.mOriginalAddress == address) {
                 builder.append(new String(info.mCharacters, 0, info.mCharacters.length));
-                result = builder.toString();
+                result = new WeightedString(builder.toString(), info.mFrequency);
                 break; // and return
             }
             if (hasChildrenAddress(info.mChildrenAddress)) {
@@ -1357,14 +1513,17 @@ public class BinaryDictInputOutput {
             int groupOffset = nodeHeadPosition + getGroupCountSize(count);
             for (int i = count; i > 0; --i) { // Scan the array of CharGroup.
                 CharGroupInfo info = readCharGroup(buffer, groupOffset, options);
+                if (isMovedGroup(info.mFlags, options)) continue;
                 ArrayList<WeightedString> shortcutTargets = info.mShortcutTargets;
                 ArrayList<WeightedString> bigrams = null;
                 if (null != info.mBigrams) {
                     bigrams = new ArrayList<WeightedString>();
                     for (PendingAttribute bigram : info.mBigrams) {
-                        final String word = getWordAtAddress(
+                        final WeightedString word = getWordAtAddress(
                                 buffer, headerSize, bigram.mAddress, options);
-                        bigrams.add(new WeightedString(word, bigram.mFrequency));
+                        final int reconstructedFrequency =
+                                reconstructBigramFrequency(word.mFrequency, bigram.mFrequency);
+                        bigrams.add(new WeightedString(word.mWord, reconstructedFrequency));
                     }
                 }
                 if (hasChildrenAddress(info.mChildrenAddress)) {
@@ -1392,7 +1551,7 @@ public class BinaryDictInputOutput {
             }
 
             // reach the end of the array.
-            if (options.mHasLinkedListNode) {
+            if (options.mSupportsDynamicUpdate) {
                 final int nextAddress = buffer.readUnsignedInt24();
                 if (nextAddress >= 0 && nextAddress < buffer.limit()) {
                     buffer.position(nextAddress);
@@ -1400,7 +1559,7 @@ public class BinaryDictInputOutput {
                     break;
                 }
             }
-        } while (options.mHasLinkedListNode &&
+        } while (options.mSupportsDynamicUpdate &&
                 buffer.position() != FormatSpec.NO_FORWARD_LINK_ADDRESS);
 
         final Node node = new Node(nodeContents);
@@ -1469,8 +1628,7 @@ public class BinaryDictInputOutput {
                         0 != (optionsFlags & FormatSpec.GERMAN_UMLAUT_PROCESSING_FLAG),
                         0 != (optionsFlags & FormatSpec.FRENCH_LIGATURE_PROCESSING_FLAG)),
                 new FormatOptions(version,
-                        0 != (optionsFlags & FormatSpec.HAS_PARENT_ADDRESS),
-                        0 != (optionsFlags & FormatSpec.HAS_LINKEDLIST_NODE)));
+                        0 != (optionsFlags & FormatSpec.SUPPORTS_DYNAMIC_UPDATE)));
         return header;
     }
 
@@ -1500,6 +1658,7 @@ public class BinaryDictInputOutput {
      * @param dict an optional dictionary to add words to, or null.
      * @return the created (or merged) dictionary.
      */
+    @UsedForTesting
     public static FusionDictionary readDictionaryBinary(
             final FusionDictionaryBufferInterface buffer, final FusionDictionary dict)
                     throws IOException, UnsupportedFormatException {
@@ -1537,17 +1696,24 @@ public class BinaryDictInputOutput {
     }
 
     /**
+     * Helper method to pass a file name instead of a File object to isBinaryDictionary.
+     */
+    public static boolean isBinaryDictionary(final String filename) {
+        final File file = new File(filename);
+        return isBinaryDictionary(file);
+    }
+
+    /**
      * Basic test to find out whether the file is a binary dictionary or not.
      *
      * Concretely this only tests the magic number.
      *
-     * @param filename The name of the file to test.
+     * @param file The file to test.
      * @return true if it's a binary dictionary, false otherwise
      */
-    public static boolean isBinaryDictionary(final String filename) {
+    public static boolean isBinaryDictionary(final File file) {
         FileInputStream inStream = null;
         try {
-            final File file = new File(filename);
             inStream = new FileInputStream(file);
             final ByteBuffer buffer = inStream.getChannel().map(
                     FileChannel.MapMode.READ_ONLY, 0, file.length());
@@ -1582,8 +1748,7 @@ public class BinaryDictInputOutput {
             final int bigramFrequency) {
         final float stepSize = (FormatSpec.MAX_TERMINAL_FREQUENCY - unigramFrequency)
                 / (1.5f + FormatSpec.MAX_BIGRAM_FREQUENCY);
-        final float resultFreqFloat = (float)unigramFrequency
-                + stepSize * (bigramFrequency + 1.0f);
+        final float resultFreqFloat = unigramFrequency + stepSize * (bigramFrequency + 1.0f);
         return (int)resultFreqFloat;
     }
 }
diff --git a/java/src/com/android/inputmethod/latin/makedict/CharGroupInfo.java b/java/src/com/android/inputmethod/latin/makedict/CharGroupInfo.java
index ed9388409..8e64082e6 100644
--- a/java/src/com/android/inputmethod/latin/makedict/CharGroupInfo.java
+++ b/java/src/com/android/inputmethod/latin/makedict/CharGroupInfo.java
@@ -23,7 +23,7 @@ import java.util.ArrayList;
 /**
  * Raw char group info straight out of a file. This will contain numbers for addresses.
  */
-public class CharGroupInfo {
+public final class CharGroupInfo {
 
     public final int mOriginalAddress;
     public final int mEndAddress;
diff --git a/java/src/com/android/inputmethod/latin/makedict/FormatSpec.java b/java/src/com/android/inputmethod/latin/makedict/FormatSpec.java
index adc6037bb..705f66414 100644
--- a/java/src/com/android/inputmethod/latin/makedict/FormatSpec.java
+++ b/java/src/com/android/inputmethod/latin/makedict/FormatSpec.java
@@ -42,32 +42,43 @@ public final class FormatSpec {
      * ps
      *
      * f |
-     * o | IF HAS_LINKEDLIST_NODE (defined in the file header)
+     * o | IF SUPPORTS_DYNAMIC_UPDATE (defined in the file header)
      * r |     forward link address, 3byte
-     * w | the address must be positive.
-     * a |
-     * rdlinkaddress
+     * w | 1 byte = bbbbbbbb match
+     * a |   case 1xxxxxxx => -((xxxxxxx << 16) + (next byte << 8) + next byte)
+     * r |   otherwise => (xxxxxxx << 16) + (next byte << 8) + next byte
+     * d |
+     * linkaddress
      */
 
     /* Node(CharGroup) layout is as follows:
-     *   | addressType                         xx     : mask with MASK_GROUP_ADDRESS_TYPE
-     *                                 2 bits, 00 = no children : FLAG_GROUP_ADDRESS_TYPE_NOADDRESS
-     * f |                                     01 = 1 byte      : FLAG_GROUP_ADDRESS_TYPE_ONEBYTE
-     * l |                                     10 = 2 bytes     : FLAG_GROUP_ADDRESS_TYPE_TWOBYTES
-     * a |                                     11 = 3 bytes     : FLAG_GROUP_ADDRESS_TYPE_THREEBYTES
-     * g | has several chars ?         1 bit, 1 = yes, 0 = no   : FLAG_HAS_MULTIPLE_CHARS
-     * s | has a terminal ?            1 bit, 1 = yes, 0 = no   : FLAG_IS_TERMINAL
+     *   | IF !SUPPORTS_DYNAMIC_UPDATE
+     *   |   addressType                         xx     : mask with MASK_GROUP_ADDRESS_TYPE
+     *   |                           2 bits, 00 = no children : FLAG_GROUP_ADDRESS_TYPE_NOADDRESS
+     * f |                                   01 = 1 byte      : FLAG_GROUP_ADDRESS_TYPE_ONEBYTE
+     * l |                                   10 = 2 bytes     : FLAG_GROUP_ADDRESS_TYPE_TWOBYTES
+     * a |                                   11 = 3 bytes     : FLAG_GROUP_ADDRESS_TYPE_THREEBYTES
+     * g | ELSE
+     * s |   is moved ?              2 bits, 11 = no          : FLAG_IS_NOT_MOVED
+     *   |                              This must be the same as FLAG_GROUP_ADDRESS_TYPE_THREEBYTES
+     *   |                                   01 = yes         : FLAG_IS_MOVED
+     *   |                        the new address is stored in the same place as the parent address
+     *   |   is deleted?                     10 = yes         : FLAG_IS_DELETED
+     *   | has several chars ?         1 bit, 1 = yes, 0 = no   : FLAG_HAS_MULTIPLE_CHARS
+     *   | has a terminal ?            1 bit, 1 = yes, 0 = no   : FLAG_IS_TERMINAL
      *   | has shortcut targets ?      1 bit, 1 = yes, 0 = no   : FLAG_HAS_SHORTCUT_TARGETS
      *   | has bigrams ?               1 bit, 1 = yes, 0 = no   : FLAG_HAS_BIGRAMS
      *   | is not a word ?             1 bit, 1 = yes, 0 = no   : FLAG_IS_NOT_A_WORD
      *   | is blacklisted ?            1 bit, 1 = yes, 0 = no   : FLAG_IS_BLACKLISTED
      *
      * p |
-     * a | IF HAS_PARENT_ADDRESS (defined in the file header)
+     * a | IF SUPPORTS_DYNAMIC_UPDATE (defined in the file header)
      * r |     parent address, 3byte
-     * e | the address must be negative, so the absolute value of the address is stored.
-     * n |
-     * taddress
+     * e | 1 byte = bbbbbbbb match
+     * n |   case 1xxxxxxx => -((0xxxxxxx << 16) + (next byte << 8) + next byte)
+     * t |   otherwise => (bbbbbbbb << 16) + (next byte << 8) + next byte
+     * a |
+     * ddress
      *
      * c | IF FLAG_HAS_MULTIPLE_CHARS
      * h |   char, char, char, char    n * (1 or 3 bytes) : use CharGroupInfo for i/o helpers
@@ -145,17 +156,14 @@ public final class FormatSpec {
     static final int MAXIMUM_SUPPORTED_VERSION = 3;
     static final int NOT_A_VERSION_NUMBER = -1;
     static final int FIRST_VERSION_WITH_HEADER_SIZE = 2;
-    static final int FIRST_VERSION_WITH_PARENT_ADDRESS = 3;
-    static final int FIRST_VERSION_WITH_LINKEDLIST_NODE = 3;
+    static final int FIRST_VERSION_WITH_DYNAMIC_UPDATE = 3;
 
     // These options need to be the same numeric values as the one in the native reading code.
     static final int GERMAN_UMLAUT_PROCESSING_FLAG = 0x1;
     // TODO: Make the native reading code read this variable.
-    static final int HAS_PARENT_ADDRESS = 0x2;
+    static final int SUPPORTS_DYNAMIC_UPDATE = 0x2;
     static final int FRENCH_LIGATURE_PROCESSING_FLAG = 0x4;
     static final int CONTAINS_BIGRAMS_FLAG = 0x8;
-    // TODO: Make the native reading code read this variable.
-    static final int HAS_LINKEDLIST_NODE = 0x10;
 
     // TODO: Make this value adaptative to content data, store it in the header, and
     // use it in the reading code.
@@ -164,6 +172,7 @@ public final class FormatSpec {
     static final int PARENT_ADDRESS_SIZE = 3;
     static final int FORWARD_LINK_ADDRESS_SIZE = 3;
 
+    // These flags are used only in the static dictionary.
     static final int MASK_GROUP_ADDRESS_TYPE = 0xC0;
     static final int FLAG_GROUP_ADDRESS_TYPE_NOADDRESS = 0x00;
     static final int FLAG_GROUP_ADDRESS_TYPE_ONEBYTE = 0x40;
@@ -178,6 +187,13 @@ public final class FormatSpec {
     static final int FLAG_IS_NOT_A_WORD = 0x02;
     static final int FLAG_IS_BLACKLISTED = 0x01;
 
+    // These flags are used only in the dynamic dictionary.
+    static final int MASK_MOVE_AND_DELETE_FLAG = 0xC0;
+    static final int FIXED_BIT_OF_DYNAMIC_UPDATE_MOVE = 0x40;
+    static final int FLAG_IS_MOVED = 0x00 | FIXED_BIT_OF_DYNAMIC_UPDATE_MOVE;
+    static final int FLAG_IS_NOT_MOVED = 0x80 | FIXED_BIT_OF_DYNAMIC_UPDATE_MOVE;
+    static final int FLAG_IS_DELETED = 0x80;
+
     static final int FLAG_ATTRIBUTE_HAS_NEXT = 0x80;
     static final int FLAG_ATTRIBUTE_OFFSET_NEGATIVE = 0x40;
     static final int MASK_ATTRIBUTE_ADDRESS_TYPE = 0x30;
@@ -203,43 +219,33 @@ public final class FormatSpec {
 
     static final int MAX_CHARGROUPS_FOR_ONE_BYTE_CHARGROUP_COUNT = 0x7F; // 127
     static final int MAX_CHARGROUPS_IN_A_NODE = 0x7FFF; // 32767
+    static final int MAX_BIGRAMS_IN_A_GROUP = 10000;
 
     static final int MAX_TERMINAL_FREQUENCY = 255;
     static final int MAX_BIGRAM_FREQUENCY = 15;
 
+    public static final int SHORTCUT_WHITELIST_FREQUENCY = 15;
+
     // This option needs to be the same numeric value as the one in binary_format.h.
     static final int NOT_VALID_WORD = -99;
+    static final int SIGNED_CHILDREN_ADDRESS_SIZE = 3;
 
     /**
      * Options about file format.
      */
-    public static class FormatOptions {
+    public static final class FormatOptions {
         public final int mVersion;
-        public final boolean mHasParentAddress;
-        public final boolean mHasLinkedListNode;
+        public final boolean mSupportsDynamicUpdate;
         public FormatOptions(final int version) {
             this(version, false);
         }
-        public FormatOptions(final int version, final boolean hasParentAddress) {
-            this(version, hasParentAddress, false);
-        }
-        public FormatOptions(final int version, final boolean hasParentAddress,
-                final boolean hasLinkedListNode) {
+        public FormatOptions(final int version, final boolean supportsDynamicUpdate) {
             mVersion = version;
-            if (version < FIRST_VERSION_WITH_PARENT_ADDRESS && hasParentAddress) {
-                throw new RuntimeException("Parent addresses are only supported with versions "
-                        + FIRST_VERSION_WITH_PARENT_ADDRESS + " and ulterior.");
-            }
-            mHasParentAddress = hasParentAddress;
-
-            if (version < FIRST_VERSION_WITH_LINKEDLIST_NODE && hasLinkedListNode) {
-                throw new RuntimeException("Linked list nodes are only supported with versions "
-                        + FIRST_VERSION_WITH_LINKEDLIST_NODE + " and ulterior.");
-            }
-            if (!hasParentAddress && hasLinkedListNode) {
-                throw new RuntimeException("Linked list nodes need parent addresses.");
+            if (version < FIRST_VERSION_WITH_DYNAMIC_UPDATE && supportsDynamicUpdate) {
+                throw new RuntimeException("Dynamic updates are only supported with versions "
+                        + FIRST_VERSION_WITH_DYNAMIC_UPDATE + " and ulterior.");
             }
-            mHasLinkedListNode = hasLinkedListNode;
+            mSupportsDynamicUpdate = supportsDynamicUpdate;
         }
     }
 
diff --git a/java/src/com/android/inputmethod/latin/makedict/FusionDictionary.java b/java/src/com/android/inputmethod/latin/makedict/FusionDictionary.java
index 98cf308c8..b0b3777df 100644
--- a/java/src/com/android/inputmethod/latin/makedict/FusionDictionary.java
+++ b/java/src/com/android/inputmethod/latin/makedict/FusionDictionary.java
@@ -21,6 +21,7 @@ import com.android.inputmethod.latin.Constants;
 import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.Collections;
+import java.util.Date;
 import java.util.HashMap;
 import java.util.Iterator;
 import java.util.LinkedList;
@@ -28,8 +29,7 @@ import java.util.LinkedList;
 /**
  * A dictionary that can fusion heads and tails of words for more compression.
  */
-public class FusionDictionary implements Iterable<Word> {
-
+public final class FusionDictionary implements Iterable<Word> {
     private static final boolean DBG = MakedictLog.DBG;
 
     /**
@@ -40,7 +40,7 @@ public class FusionDictionary implements Iterable<Word> {
      * This class also contains fields to cache size and address, to help with binary
      * generation.
      */
-    public static class Node {
+    public static final class Node {
         ArrayList<CharGroup> mData;
         // To help with binary generation
         int mCachedSize = Integer.MIN_VALUE;
@@ -60,7 +60,7 @@ public class FusionDictionary implements Iterable<Word> {
      *
      * This represents an "attribute", that is either a bigram or a shortcut.
      */
-    public static class WeightedString {
+    public static final class WeightedString {
         public final String mWord;
         public int mFrequency;
         public WeightedString(String word, int frequency) {
@@ -94,7 +94,7 @@ public class FusionDictionary implements Iterable<Word> {
      * value is the frequency of this terminal. A terminal may have non-null shortcuts and/or
      * bigrams, but a non-terminal may not. Moreover, children, if present, are null.
      */
-    public static class CharGroup {
+    public static final class CharGroup {
         public static final int NOT_A_TERMINAL = -1;
         final int mChars[];
         ArrayList<WeightedString> mShortcutTargets;
@@ -142,6 +142,33 @@ public class FusionDictionary implements Iterable<Word> {
             return NOT_A_TERMINAL != mFrequency;
         }
 
+        public int getFrequency() {
+            return mFrequency;
+        }
+
+        public boolean getIsNotAWord() {
+            return mIsNotAWord;
+        }
+
+        public boolean getIsBlacklistEntry() {
+            return mIsBlacklistEntry;
+        }
+
+        public ArrayList<WeightedString> getShortcutTargets() {
+            // We don't want write permission to escape outside the package, so we return a copy
+            if (null == mShortcutTargets) return null;
+            final ArrayList<WeightedString> copyOfShortcutTargets =
+                    new ArrayList<WeightedString>(mShortcutTargets);
+            return copyOfShortcutTargets;
+        }
+
+        public ArrayList<WeightedString> getBigrams() {
+            // We don't want write permission to escape outside the package, so we return a copy
+            if (null == mBigrams) return null;
+            final ArrayList<WeightedString> copyOfBigrams = new ArrayList<WeightedString>(mBigrams);
+            return copyOfBigrams;
+        }
+
         public boolean hasSeveralChars() {
             assert(mChars.length > 0);
             return 1 < mChars.length;
@@ -250,10 +277,8 @@ public class FusionDictionary implements Iterable<Word> {
 
     /**
      * Options global to the dictionary.
-     *
-     * There are no options at the moment, so this class is empty.
      */
-    public static class DictionaryOptions {
+    public static final class DictionaryOptions {
         public final boolean mGermanUmlautProcessing;
         public final boolean mFrenchLigatureProcessing;
         public final HashMap<String, String> mAttributes;
@@ -263,6 +288,43 @@ public class FusionDictionary implements Iterable<Word> {
             mGermanUmlautProcessing = germanUmlautProcessing;
             mFrenchLigatureProcessing = frenchLigatureProcessing;
         }
+        @Override
+        public String toString() { // Convenience method
+            return toString(0, false);
+        }
+        public String toString(final int indentCount, final boolean plumbing) {
+            final StringBuilder indent = new StringBuilder();
+            if (plumbing) {
+                indent.append("H:");
+            } else {
+                for (int i = 0; i < indentCount; ++i) {
+                    indent.append(" ");
+                }
+            }
+            final StringBuilder s = new StringBuilder();
+            for (final String optionKey : mAttributes.keySet()) {
+                s.append(indent);
+                s.append(optionKey);
+                s.append(" = ");
+                if ("date".equals(optionKey) && !plumbing) {
+                    // Date needs a number of milliseconds, but the dictionary contains seconds
+                    s.append(new Date(
+                            1000 * Long.parseLong(mAttributes.get(optionKey))).toString());
+                } else {
+                    s.append(mAttributes.get(optionKey));
+                }
+                s.append("\n");
+            }
+            if (mGermanUmlautProcessing) {
+                s.append(indent);
+                s.append("Needs German umlaut processing\n");
+            }
+            if (mFrenchLigatureProcessing) {
+                s.append(indent);
+                s.append("Needs French ligature processing\n");
+            }
+            return s.toString();
+        }
     }
 
     public final DictionaryOptions mOptions;
@@ -280,7 +342,7 @@ public class FusionDictionary implements Iterable<Word> {
     /**
      * Helper method to convert a String to an int array.
      */
-    static private int[] getCodePoints(final String word) {
+    static int[] getCodePoints(final String word) {
         // TODO: this is a copy-paste of the contents of StringUtils.toCodePointArray,
         // which is not visible from the makedict package. Factor this code.
         final char[] characters = word.toCharArray();
@@ -359,6 +421,10 @@ public class FusionDictionary implements Iterable<Word> {
             if (charGroup2 == null) {
                 add(getCodePoints(word2), 0, null, false /* isNotAWord */,
                         false /* isBlacklistEntry */);
+                // The chargroup for the first word may have moved by the above insertion,
+                // if word1 and word2 share a common stem that happens not to have been
+                // a cutting point until now. In this case, we need to refresh charGroup.
+                charGroup = findWordInTree(mRoot, word1);
             }
             charGroup.addBigram(word2, frequency);
         } else {
@@ -511,7 +577,7 @@ public class FusionDictionary implements Iterable<Word> {
      * is ignored.
      * This comparator imposes orderings that are inconsistent with equals.
      */
-    static private class CharGroupComparator implements java.util.Comparator<CharGroup> {
+    static private final class CharGroupComparator implements java.util.Comparator<CharGroup> {
         @Override
         public int compare(CharGroup c1, CharGroup c2) {
             if (c1.mChars[0] == c2.mChars[0]) return 0;
@@ -746,9 +812,8 @@ public class FusionDictionary implements Iterable<Word> {
      *
      * This is purely for convenience.
      */
-    public static class DictionaryIterator implements Iterator<Word> {
-
-        private static class Position {
+    public static final class DictionaryIterator implements Iterator<Word> {
+        private static final class Position {
             public Iterator<CharGroup> pos;
             public int length;
             public Position(ArrayList<CharGroup> groups) {
diff --git a/java/src/com/android/inputmethod/latin/makedict/MakedictLog.java b/java/src/com/android/inputmethod/latin/makedict/MakedictLog.java
index 3f0cd0796..6c6b00b6a 100644
--- a/java/src/com/android/inputmethod/latin/makedict/MakedictLog.java
+++ b/java/src/com/android/inputmethod/latin/makedict/MakedictLog.java
@@ -21,7 +21,7 @@ import android.util.Log;
 /**
  * Wrapper to redirect log events to the right output medium.
  */
-public class MakedictLog {
+public final class MakedictLog {
     public static final boolean DBG = false;
     private static final String TAG = MakedictLog.class.getSimpleName();
 
diff --git a/java/src/com/android/inputmethod/latin/makedict/PendingAttribute.java b/java/src/com/android/inputmethod/latin/makedict/PendingAttribute.java
index 5b41d27f2..5bb24da74 100644
--- a/java/src/com/android/inputmethod/latin/makedict/PendingAttribute.java
+++ b/java/src/com/android/inputmethod/latin/makedict/PendingAttribute.java
@@ -22,7 +22,7 @@ package com.android.inputmethod.latin.makedict;
  * An attribute is either a bigram or a shortcut.
  * All instances of this class are always immutable.
  */
-public class PendingAttribute {
+public final class PendingAttribute {
     public final int mFrequency;
     public final int mAddress;
     public PendingAttribute(final int frequency, final int address) {
diff --git a/java/src/com/android/inputmethod/latin/makedict/UnsupportedFormatException.java b/java/src/com/android/inputmethod/latin/makedict/UnsupportedFormatException.java
index bd42fb8fa..dbb2ea870 100644
--- a/java/src/com/android/inputmethod/latin/makedict/UnsupportedFormatException.java
+++ b/java/src/com/android/inputmethod/latin/makedict/UnsupportedFormatException.java
@@ -19,7 +19,7 @@ package com.android.inputmethod.latin.makedict;
 /**
  * Simple exception thrown when a file format is not recognized.
  */
-public class UnsupportedFormatException extends Exception {
+public final class UnsupportedFormatException extends Exception {
     public UnsupportedFormatException(String description) {
         super(description);
     }
diff --git a/java/src/com/android/inputmethod/latin/makedict/Word.java b/java/src/com/android/inputmethod/latin/makedict/Word.java
index 4683ef154..4c4f18f1a 100644
--- a/java/src/com/android/inputmethod/latin/makedict/Word.java
+++ b/java/src/com/android/inputmethod/latin/makedict/Word.java
@@ -26,7 +26,7 @@ import java.util.Arrays;
  *
  * This is chiefly used to iterate a dictionary.
  */
-public class Word implements Comparable<Word> {
+public final class Word implements Comparable<Word> {
     public final String mWord;
     public final int mFrequency;
     public final ArrayList<WeightedString> mShortcutTargets;
diff --git a/java/src/com/android/inputmethod/latin/spellcheck/AndroidSpellCheckerService.java b/java/src/com/android/inputmethod/latin/spellcheck/AndroidSpellCheckerService.java
index eef7a51f2..49b98863f 100644
--- a/java/src/com/android/inputmethod/latin/spellcheck/AndroidSpellCheckerService.java
+++ b/java/src/com/android/inputmethod/latin/spellcheck/AndroidSpellCheckerService.java
@@ -50,7 +50,7 @@ import java.util.TreeMap;
 /**
  * Service for spell checking, using LatinIME's dictionaries and mechanisms.
  */
-public class AndroidSpellCheckerService extends SpellCheckerService
+public final class AndroidSpellCheckerService extends SpellCheckerService
         implements SharedPreferences.OnSharedPreferenceChangeListener {
     private static final String TAG = AndroidSpellCheckerService.class.getSimpleName();
     private static final boolean DBG = false;
@@ -201,8 +201,8 @@ public class AndroidSpellCheckerService extends SpellCheckerService
     }
 
     // TODO: remove this class and replace it by storage local to the session.
-    public static class SuggestionsGatherer {
-        public static class Result {
+    public static final class SuggestionsGatherer {
+        public static final class Result {
             public final String[] mSuggestions;
             public final boolean mHasRecommendedSuggestions;
             public Result(final String[] gatheredSuggestions,
@@ -212,7 +212,7 @@ public class AndroidSpellCheckerService extends SpellCheckerService
             }
         }
 
-        private final ArrayList<CharSequence> mSuggestions;
+        private final ArrayList<String> mSuggestions;
         private final int[] mScores;
         private final String mOriginalText;
         private final float mSuggestionThreshold;
@@ -335,7 +335,7 @@ public class AndroidSpellCheckerService extends SpellCheckerService
                 gatheredSuggestions = mSuggestions.toArray(EMPTY_STRING_ARRAY);
 
                 final int bestScore = mScores[mLength - 1];
-                final CharSequence bestSuggestion = mSuggestions.get(0);
+                final String bestSuggestion = mSuggestions.get(0);
                 final float normalizedScore =
                         BinaryDictionary.calcNormalizedScore(
                                 mOriginalText, bestSuggestion.toString(), bestScore);
diff --git a/java/src/com/android/inputmethod/latin/spellcheck/AndroidSpellCheckerSession.java b/java/src/com/android/inputmethod/latin/spellcheck/AndroidSpellCheckerSession.java
index 5a1bd37f5..668e7a641 100644
--- a/java/src/com/android/inputmethod/latin/spellcheck/AndroidSpellCheckerSession.java
+++ b/java/src/com/android/inputmethod/latin/spellcheck/AndroidSpellCheckerSession.java
@@ -26,7 +26,7 @@ import com.android.inputmethod.latin.CollectionUtils;
 
 import java.util.ArrayList;
 
-public class AndroidSpellCheckerSession extends AndroidWordLevelSpellCheckerSession {
+public final class AndroidSpellCheckerSession extends AndroidWordLevelSpellCheckerSession {
     private static final String TAG = AndroidSpellCheckerSession.class.getSimpleName();
     private static final boolean DBG = false;
     private final static String[] EMPTY_STRING_ARRAY = new String[0];
diff --git a/java/src/com/android/inputmethod/latin/spellcheck/AndroidWordLevelSpellCheckerSession.java b/java/src/com/android/inputmethod/latin/spellcheck/AndroidWordLevelSpellCheckerSession.java
index d9b622a18..a8f323999 100644
--- a/java/src/com/android/inputmethod/latin/spellcheck/AndroidWordLevelSpellCheckerSession.java
+++ b/java/src/com/android/inputmethod/latin/spellcheck/AndroidWordLevelSpellCheckerSession.java
@@ -50,7 +50,7 @@ public abstract class AndroidWordLevelSpellCheckerSession extends Session {
     protected final SuggestionsCache mSuggestionsCache = new SuggestionsCache();
     private final ContentObserver mObserver;
 
-    private static class SuggestionsParams {
+    private static final class SuggestionsParams {
         public final String[] mSuggestions;
         public final int mFlags;
         public SuggestionsParams(String[] suggestions, int flags) {
@@ -59,7 +59,7 @@ public abstract class AndroidWordLevelSpellCheckerSession extends Session {
         }
     }
 
-    protected static class SuggestionsCache {
+    protected static final class SuggestionsCache {
         private static final char CHAR_DELIMITER = '\uFFFC';
         private static final int MAX_CACHE_SIZE = 50;
         private final LruCache<String, SuggestionsParams> mUnigramSuggestionsInfoCache =
@@ -268,7 +268,7 @@ public abstract class AndroidWordLevelSpellCheckerSession extends Session {
                         dictInfo.mDictionary.getSuggestions(composer, prevWord,
                                 dictInfo.mProximityInfo);
                 for (final SuggestedWordInfo suggestion : suggestions) {
-                    final String suggestionStr = suggestion.mWord.toString();
+                    final String suggestionStr = suggestion.mWord;
                     suggestionsGatherer.addWord(suggestionStr.toCharArray(), null, 0,
                             suggestionStr.length(), suggestion.mScore);
                 }
diff --git a/java/src/com/android/inputmethod/latin/spellcheck/DictAndProximity.java b/java/src/com/android/inputmethod/latin/spellcheck/DictAndProximity.java
index 3dbbd40cd..9d7c61a33 100644
--- a/java/src/com/android/inputmethod/latin/spellcheck/DictAndProximity.java
+++ b/java/src/com/android/inputmethod/latin/spellcheck/DictAndProximity.java
@@ -22,7 +22,7 @@ import com.android.inputmethod.keyboard.ProximityInfo;
 /**
  * A simple container for both a Dictionary and a ProximityInfo.
  */
-public class DictAndProximity {
+public final class DictAndProximity {
     public final Dictionary mDictionary;
     public final ProximityInfo mProximityInfo;
     public DictAndProximity(final Dictionary dictionary, final ProximityInfo proximityInfo) {
diff --git a/java/src/com/android/inputmethod/latin/spellcheck/DictionaryPool.java b/java/src/com/android/inputmethod/latin/spellcheck/DictionaryPool.java
index 53aa6c719..eae5d2e60 100644
--- a/java/src/com/android/inputmethod/latin/spellcheck/DictionaryPool.java
+++ b/java/src/com/android/inputmethod/latin/spellcheck/DictionaryPool.java
@@ -36,7 +36,7 @@ import java.util.concurrent.TimeUnit;
  * the client code, but may help with sloppy clients.
  */
 @SuppressWarnings("serial")
-public class DictionaryPool extends LinkedBlockingQueue<DictAndProximity> {
+public final class DictionaryPool extends LinkedBlockingQueue<DictAndProximity> {
     private final static String TAG = DictionaryPool.class.getSimpleName();
     // How many seconds we wait for a dictionary to become available. Past this delay, we give up in
     // fear some bug caused a deadlock, and reset the whole pool.
@@ -51,11 +51,11 @@ public class DictionaryPool extends LinkedBlockingQueue<DictAndProximity> {
             new Dictionary(Dictionary.TYPE_MAIN) {
                 @Override
                 public ArrayList<SuggestedWordInfo> getSuggestions(final WordComposer composer,
-                        final CharSequence prevWord, final ProximityInfo proximityInfo) {
+                        final String prevWord, final ProximityInfo proximityInfo) {
                     return noSuggestions;
                 }
                 @Override
-                public boolean isValidWord(CharSequence word) {
+                public boolean isValidWord(final String word) {
                     // This is never called. However if for some strange reason it ever gets
                     // called, returning true is less destructive (it will not underline the
                     // word in red).
diff --git a/java/src/com/android/inputmethod/latin/spellcheck/SpellCheckerProximityInfo.java b/java/src/com/android/inputmethod/latin/spellcheck/SpellCheckerProximityInfo.java
index fe5225ebd..6c0d79c2b 100644
--- a/java/src/com/android/inputmethod/latin/spellcheck/SpellCheckerProximityInfo.java
+++ b/java/src/com/android/inputmethod/latin/spellcheck/SpellCheckerProximityInfo.java
@@ -16,14 +16,15 @@
 
 package com.android.inputmethod.latin.spellcheck;
 
+import com.android.inputmethod.annotations.UsedForTesting;
 import com.android.inputmethod.keyboard.ProximityInfo;
 import com.android.inputmethod.latin.CollectionUtils;
 import com.android.inputmethod.latin.Constants;
 
 import java.util.TreeMap;
 
-public class SpellCheckerProximityInfo {
-    /* public for test */
+public final class SpellCheckerProximityInfo {
+    @UsedForTesting
     final public static int NUL = Constants.NOT_A_CODE;
 
     // This must be the same as MAX_PROXIMITY_CHARS_SIZE else it will not work inside
@@ -53,7 +54,7 @@ public class SpellCheckerProximityInfo {
         return result;
     }
 
-    private static class Latin {
+    private static final class Latin {
         // This is a map from the code point to the index in the PROXIMITY array.
         // At the time the native code to read the binary dictionary needs the proximity info be
         // passed as a flat array spaced by MAX_PROXIMITY_CHARS_SIZE columns, one for each input
@@ -122,7 +123,7 @@ public class SpellCheckerProximityInfo {
         }
     }
 
-    private static class Cyrillic {
+    private static final class Cyrillic {
         final private static TreeMap<Integer, Integer> INDICES = CollectionUtils.newTreeMap();
         // TODO: The following table is solely based on the keyboard layout. Consult with Russian
         // speakers on commonly misspelled words/letters.
diff --git a/java/src/com/android/inputmethod/latin/spellcheck/SpellCheckerSettingsActivity.java b/java/src/com/android/inputmethod/latin/spellcheck/SpellCheckerSettingsActivity.java
index e14db8797..e63dff312 100644
--- a/java/src/com/android/inputmethod/latin/spellcheck/SpellCheckerSettingsActivity.java
+++ b/java/src/com/android/inputmethod/latin/spellcheck/SpellCheckerSettingsActivity.java
@@ -23,7 +23,7 @@ import android.preference.PreferenceActivity;
 /**
  * Spell checker preference screen.
  */
-public class SpellCheckerSettingsActivity extends PreferenceActivity {
+public final class SpellCheckerSettingsActivity extends PreferenceActivity {
     @Override
     protected void onCreate(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
diff --git a/java/src/com/android/inputmethod/latin/spellcheck/SpellCheckerSettingsFragment.java b/java/src/com/android/inputmethod/latin/spellcheck/SpellCheckerSettingsFragment.java
index 7056874a1..ef5123d68 100644
--- a/java/src/com/android/inputmethod/latin/spellcheck/SpellCheckerSettingsFragment.java
+++ b/java/src/com/android/inputmethod/latin/spellcheck/SpellCheckerSettingsFragment.java
@@ -24,7 +24,7 @@ import com.android.inputmethod.latin.R;
 /**
  * Preference screen.
  */
-public class SpellCheckerSettingsFragment extends PreferenceFragment {
+public final class SpellCheckerSettingsFragment extends PreferenceFragment {
     /**
      * Empty constructor for fragment generation.
      */
diff --git a/java/src/com/android/inputmethod/latin/suggestions/MoreSuggestions.java b/java/src/com/android/inputmethod/latin/suggestions/MoreSuggestions.java
index 1f883aa60..35d5a0067 100644
--- a/java/src/com/android/inputmethod/latin/suggestions/MoreSuggestions.java
+++ b/java/src/com/android/inputmethod/latin/suggestions/MoreSuggestions.java
@@ -22,7 +22,6 @@ import android.graphics.drawable.Drawable;
 
 import com.android.inputmethod.keyboard.Key;
 import com.android.inputmethod.keyboard.Keyboard;
-import com.android.inputmethod.keyboard.KeyboardSwitcher;
 import com.android.inputmethod.keyboard.internal.KeyboardBuilder;
 import com.android.inputmethod.keyboard.internal.KeyboardIconsSet;
 import com.android.inputmethod.keyboard.internal.KeyboardParams;
@@ -30,14 +29,14 @@ import com.android.inputmethod.latin.R;
 import com.android.inputmethod.latin.SuggestedWords;
 import com.android.inputmethod.latin.Utils;
 
-public class MoreSuggestions extends Keyboard {
+public final class MoreSuggestions extends Keyboard {
     public static final int SUGGESTION_CODE_BASE = 1024;
 
     MoreSuggestions(final MoreSuggestionsParam params) {
         super(params);
     }
 
-    private static class MoreSuggestionsParam extends KeyboardParams {
+    private static final class MoreSuggestionsParam extends KeyboardParams {
         private final int[] mWidths = new int[SuggestionStripView.MAX_SUGGESTIONS];
         private final int[] mRowNumbers = new int[SuggestionStripView.MAX_SUGGESTIONS];
         private final int[] mColumnOrders = new int[SuggestionStripView.MAX_SUGGESTIONS];
@@ -51,10 +50,11 @@ public class MoreSuggestions extends Keyboard {
             super();
         }
 
+        // TODO: Remove {@link MoreSuggestionsView} argument.
         public int layout(final SuggestedWords suggestions, final int fromPos, final int maxWidth,
                 final int minWidth, final int maxRow, final MoreSuggestionsView view) {
             clearKeys();
-            final Resources res = view.getContext().getResources();
+            final Resources res = view.getResources();
             mDivider = res.getDrawable(R.drawable.more_suggestions_divider);
             mDividerWidth = mDivider.getIntrinsicWidth();
             final int padding = (int) res.getDimension(
@@ -65,7 +65,7 @@ public class MoreSuggestions extends Keyboard {
             int pos = fromPos, rowStartPos = fromPos;
             final int size = Math.min(suggestions.size(), SuggestionStripView.MAX_SUGGESTIONS);
             while (pos < size) {
-                final String word = suggestions.getWord(pos).toString();
+                final String word = suggestions.getWord(pos);
                 // TODO: Should take care of text x-scaling.
                 mWidths[pos] = (int)view.getLabelWidth(word, paint) + padding;
                 final int numColumn = pos - rowStartPos + 1;
@@ -163,7 +163,7 @@ public class MoreSuggestions extends Keyboard {
         }
     }
 
-    public static class Builder extends KeyboardBuilder<MoreSuggestionsParam> {
+    public static final class Builder extends KeyboardBuilder<MoreSuggestionsParam> {
         private final MoreSuggestionsView mPaneView;
         private SuggestedWords mSuggestions;
         private int mFromPos;
@@ -175,12 +175,13 @@ public class MoreSuggestions extends Keyboard {
         }
 
         public Builder layout(final SuggestedWords suggestions, final int fromPos,
-                final int maxWidth, final int minWidth, final int maxRow) {
-            final Keyboard keyboard = KeyboardSwitcher.getInstance().getKeyboard();
+                final int maxWidth, final int minWidth, final int maxRow,
+                final Keyboard parentKeyboard) {
             final int xmlId = R.xml.kbd_suggestions_pane_template;
-            load(xmlId, keyboard.mId);
-            mParams.mVerticalGap = mParams.mTopPadding = keyboard.mVerticalGap / 2;
+            load(xmlId, parentKeyboard.mId);
+            mParams.mVerticalGap = mParams.mTopPadding = parentKeyboard.mVerticalGap / 2;
 
+            mPaneView.updateKeyboardGeometry(mParams.mDefaultRowHeight);
             final int count = mParams.layout(suggestions, fromPos, maxWidth, minWidth, maxRow,
                     mPaneView);
             mFromPos = fromPos;
@@ -216,7 +217,7 @@ public class MoreSuggestions extends Keyboard {
         }
     }
 
-    private static class Divider extends Key.Spacer {
+    private static final class Divider extends Key.Spacer {
         private final Drawable mIcon;
 
         public Divider(final KeyboardParams params, final Drawable icon, final int x,
diff --git a/java/src/com/android/inputmethod/latin/suggestions/MoreSuggestionsView.java b/java/src/com/android/inputmethod/latin/suggestions/MoreSuggestionsView.java
index 5b23d7f3c..6cdd9e2cd 100644
--- a/java/src/com/android/inputmethod/latin/suggestions/MoreSuggestionsView.java
+++ b/java/src/com/android/inputmethod/latin/suggestions/MoreSuggestionsView.java
@@ -40,7 +40,7 @@ import com.android.inputmethod.latin.R;
  * A view that renders a virtual {@link MoreSuggestions}. It handles rendering of keys and detecting
  * key presses and touch movements.
  */
-public class MoreSuggestionsView extends KeyboardView implements MoreKeysPanel {
+public final class MoreSuggestionsView extends KeyboardView implements MoreKeysPanel {
     private final int[] mCoordinates = new int[2];
 
     final KeyDetector mModalPanelKeyDetector;
@@ -56,17 +56,17 @@ public class MoreSuggestionsView extends KeyboardView implements MoreKeysPanel {
     final KeyboardActionListener mSuggestionsPaneListener =
             new KeyboardActionListener.Adapter() {
         @Override
-        public void onPressKey(int primaryCode) {
+        public void onPressKey(final int primaryCode) {
             mListener.onPressKey(primaryCode);
         }
 
         @Override
-        public void onReleaseKey(int primaryCode, boolean withSliding) {
+        public void onReleaseKey(final int primaryCode, final boolean withSliding) {
             mListener.onReleaseKey(primaryCode, withSliding);
         }
 
         @Override
-        public void onCodeInput(int primaryCode, int x, int y) {
+        public void onCodeInput(final int primaryCode, final int x, final int y) {
             final int index = primaryCode - MoreSuggestions.SUGGESTION_CODE_BASE;
             if (index >= 0 && index < SuggestionStripView.MAX_SUGGESTIONS) {
                 mListener.onCustomRequest(index);
@@ -79,11 +79,12 @@ public class MoreSuggestionsView extends KeyboardView implements MoreKeysPanel {
         }
     };
 
-    public MoreSuggestionsView(Context context, AttributeSet attrs) {
+    public MoreSuggestionsView(final Context context, final AttributeSet attrs) {
         this(context, attrs, R.attr.moreSuggestionsViewStyle);
     }
 
-    public MoreSuggestionsView(Context context, AttributeSet attrs, int defStyle) {
+    public MoreSuggestionsView(final Context context, final AttributeSet attrs,
+            final int defStyle) {
         super(context, attrs, defStyle);
 
         final Resources res = context.getResources();
@@ -94,7 +95,7 @@ public class MoreSuggestionsView extends KeyboardView implements MoreKeysPanel {
     }
 
     @Override
-    protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
+    protected void onMeasure(final int widthMeasureSpec, final int heightMeasureSpec) {
         final Keyboard keyboard = getKeyboard();
         if (keyboard != null) {
             final int width = keyboard.mOccupiedWidth + getPaddingLeft() + getPaddingRight();
@@ -105,8 +106,12 @@ public class MoreSuggestionsView extends KeyboardView implements MoreKeysPanel {
         }
     }
 
+    public void updateKeyboardGeometry(final int keyHeight) {
+        mKeyDrawParams.updateParams(keyHeight, mKeyVisualAttributes);
+    }
+
     @Override
-    public void setKeyboard(Keyboard keyboard) {
+    public void setKeyboard(final Keyboard keyboard) {
         super.setKeyboard(keyboard);
         mModalPanelKeyDetector.setKeyboard(keyboard, -getPaddingLeft(), -getPaddingTop());
         mSlidingPanelKeyDetector.setKeyboard(keyboard, -getPaddingLeft(),
@@ -134,15 +139,16 @@ public class MoreSuggestionsView extends KeyboardView implements MoreKeysPanel {
     }
 
     @Override
-    public void setKeyPreviewPopupEnabled(boolean previewEnabled, int delay) {
+    public void setKeyPreviewPopupEnabled(final boolean previewEnabled, final int delay) {
         // Suggestions pane needs no pop-up key preview displayed, so we pass always false with a
         // delay of 0. The delay does not matter actually since the popup is not shown anyway.
         super.setKeyPreviewPopupEnabled(false, 0);
     }
 
     @Override
-    public void showMoreKeysPanel(View parentView, Controller controller, int pointX, int pointY,
-            PopupWindow window, KeyboardActionListener listener) {
+    public void showMoreKeysPanel(final View parentView, final Controller controller,
+            final int pointX, final int pointY, final PopupWindow window,
+            final KeyboardActionListener listener) {
         mController = controller;
         mListener = listener;
         final View container = (View)getParent();
@@ -175,12 +181,12 @@ public class MoreSuggestionsView extends KeyboardView implements MoreKeysPanel {
     }
 
     @Override
-    public int translateX(int x) {
+    public int translateX(final int x) {
         return x - mOriginX;
     }
 
     @Override
-    public int translateY(int y) {
+    public int translateY(final int y) {
         return y - mOriginY;
     }
 
@@ -207,7 +213,7 @@ public class MoreSuggestionsView extends KeyboardView implements MoreKeysPanel {
     };
 
     @Override
-    public boolean onTouchEvent(MotionEvent me) {
+    public boolean onTouchEvent(final MotionEvent me) {
         final int action = me.getAction();
         final long eventTime = me.getEventTime();
         final int index = me.getActionIndex();
diff --git a/java/src/com/android/inputmethod/latin/suggestions/SuggestionStripView.java b/java/src/com/android/inputmethod/latin/suggestions/SuggestionStripView.java
index 9e8ab81b0..e7cb97fc2 100644
--- a/java/src/com/android/inputmethod/latin/suggestions/SuggestionStripView.java
+++ b/java/src/com/android/inputmethod/latin/suggestions/SuggestionStripView.java
@@ -52,13 +52,16 @@ import android.widget.PopupWindow;
 import android.widget.RelativeLayout;
 import android.widget.TextView;
 
+import com.android.inputmethod.keyboard.Keyboard;
 import com.android.inputmethod.keyboard.KeyboardActionListener;
+import com.android.inputmethod.keyboard.KeyboardSwitcher;
 import com.android.inputmethod.keyboard.KeyboardView;
 import com.android.inputmethod.keyboard.MoreKeysPanel;
 import com.android.inputmethod.keyboard.PointerTracker;
 import com.android.inputmethod.keyboard.ViewLayoutUtils;
 import com.android.inputmethod.latin.AutoCorrection;
 import com.android.inputmethod.latin.CollectionUtils;
+import com.android.inputmethod.latin.Constants;
 import com.android.inputmethod.latin.LatinImeLogger;
 import com.android.inputmethod.latin.R;
 import com.android.inputmethod.latin.ResourceUtils;
@@ -70,11 +73,11 @@ import com.android.inputmethod.research.ResearchLogger;
 
 import java.util.ArrayList;
 
-public class SuggestionStripView extends RelativeLayout implements OnClickListener,
+public final class SuggestionStripView extends RelativeLayout implements OnClickListener,
         OnLongClickListener {
     public interface Listener {
         public boolean addWordToUserDictionary(String word);
-        public void pickSuggestionManually(int index, CharSequence word);
+        public void pickSuggestionManually(int index, String word);
     }
 
     // The maximum number of suggestions available. See {@link Suggest#mPrefMaxSuggestions}.
@@ -83,7 +86,7 @@ public class SuggestionStripView extends RelativeLayout implements OnClickListen
     static final boolean DBG = LatinImeLogger.sDBG;
 
     private final ViewGroup mSuggestionsStrip;
-    private KeyboardView mKeyboardView;
+    KeyboardView mKeyboardView;
 
     private final View mMoreSuggestionsContainer;
     private final MoreSuggestionsView mMoreSuggestionsView;
@@ -97,23 +100,23 @@ public class SuggestionStripView extends RelativeLayout implements OnClickListen
     private final PopupWindow mPreviewPopup;
     private final TextView mPreviewText;
 
-    private Listener mListener;
-    private SuggestedWords mSuggestedWords = SuggestedWords.EMPTY;
+    Listener mListener;
+    SuggestedWords mSuggestedWords = SuggestedWords.EMPTY;
 
     private final SuggestionStripViewParams mParams;
     private static final float MIN_TEXT_XSCALE = 0.70f;
 
     private final UiHandler mHandler = new UiHandler(this);
 
-    private static class UiHandler extends StaticInnerHandlerWrapper<SuggestionStripView> {
+    private static final class UiHandler extends StaticInnerHandlerWrapper<SuggestionStripView> {
         private static final int MSG_HIDE_PREVIEW = 0;
 
-        public UiHandler(SuggestionStripView outerInstance) {
+        public UiHandler(final SuggestionStripView outerInstance) {
             super(outerInstance);
         }
 
         @Override
-        public void dispatchMessage(Message msg) {
+        public void dispatchMessage(final Message msg) {
             final SuggestionStripView suggestionStripView = getOuterInstance();
             switch (msg.what) {
             case MSG_HIDE_PREVIEW:
@@ -131,7 +134,7 @@ public class SuggestionStripView extends RelativeLayout implements OnClickListen
         }
     }
 
-    private static class SuggestionStripViewParams {
+    private static final class SuggestionStripViewParams {
         private static final int DEFAULT_SUGGESTIONS_COUNT_IN_STRIP = 3;
         private static final float DEFAULT_CENTER_SUGGESTION_PERCENTILE = 0.40f;
         private static final int DEFAULT_MAX_MORE_SUGGESTIONS_ROW = 2;
@@ -177,8 +180,9 @@ public class SuggestionStripView extends RelativeLayout implements OnClickListen
         private final TextView mLeftwardsArrowView;
         private final TextView mHintToSaveView;
 
-        public SuggestionStripViewParams(Context context, AttributeSet attrs, int defStyle,
-                ArrayList<TextView> words, ArrayList<View> dividers, ArrayList<TextView> infos) {
+        public SuggestionStripViewParams(final Context context, final AttributeSet attrs,
+                final int defStyle, final ArrayList<TextView> words, final ArrayList<View> dividers,
+                final ArrayList<TextView> infos) {
             mWords = words;
             mDividers = dividers;
             mInfos = infos;
@@ -250,7 +254,7 @@ public class SuggestionStripView extends RelativeLayout implements OnClickListen
             return mMaxMoreSuggestionsRow * mMoreSuggestionsRowHeight + mMoreSuggestionsBottomGap;
         }
 
-        public int setMoreSuggestionsHeight(int remainingHeight) {
+        public int setMoreSuggestionsHeight(final int remainingHeight) {
             final int currentHeight = getMoreSuggestionsHeight();
             if (currentHeight <= remainingHeight) {
                 return currentHeight;
@@ -262,7 +266,8 @@ public class SuggestionStripView extends RelativeLayout implements OnClickListen
             return newHeight;
         }
 
-        private static Drawable getMoreSuggestionsHint(Resources res, float textSize, int color) {
+        private static Drawable getMoreSuggestionsHint(final Resources res, final float textSize,
+                final int color) {
             final Paint paint = new Paint();
             paint.setAntiAlias(true);
             paint.setTextAlign(Align.CENTER);
@@ -279,8 +284,9 @@ public class SuggestionStripView extends RelativeLayout implements OnClickListen
             return new BitmapDrawable(res, buffer);
         }
 
-        private CharSequence getStyledSuggestionWord(SuggestedWords suggestedWords, int pos) {
-            final CharSequence word = suggestedWords.getWord(pos);
+        private CharSequence getStyledSuggestionWord(final SuggestedWords suggestedWords,
+                final int pos) {
+            final String word = suggestedWords.getWord(pos);
             final boolean isAutoCorrect = pos == 1 && suggestedWords.willAutoCorrect();
             final boolean isTypedWordValid = pos == 0 && suggestedWords.mTypedWordValid;
             if (!isAutoCorrect && !isTypedWordValid)
@@ -299,7 +305,7 @@ public class SuggestionStripView extends RelativeLayout implements OnClickListen
             return spannedWord;
         }
 
-        private int getWordPosition(int index, SuggestedWords suggestedWords) {
+        private int getWordPosition(final int index, final SuggestedWords suggestedWords) {
             // TODO: This works for 3 suggestions. Revisit this algorithm when there are 5 or more
             // suggestions.
             final int centerPos = suggestedWords.willAutoCorrect() ? 1 : 0;
@@ -312,7 +318,8 @@ public class SuggestionStripView extends RelativeLayout implements OnClickListen
             }
         }
 
-        private int getSuggestionTextColor(int index, SuggestedWords suggestedWords, int pos) {
+        private int getSuggestionTextColor(final int index, final SuggestedWords suggestedWords,
+                final int pos) {
             // TODO: Need to revisit this logic with bigram suggestions
             final boolean isSuggested = (pos != 0);
 
@@ -331,7 +338,7 @@ public class SuggestionStripView extends RelativeLayout implements OnClickListen
                 // is in slot 1.
                 if (index == mCenterSuggestionIndex
                         && AutoCorrection.shouldBlockAutoCorrectionBySafetyNet(
-                                suggestedWords.getWord(1).toString(), suggestedWords.getWord(0))) {
+                                suggestedWords.getWord(1), suggestedWords.getWord(0))) {
                     return 0xFFFF0000;
                 }
             }
@@ -355,8 +362,8 @@ public class SuggestionStripView extends RelativeLayout implements OnClickListen
             params.gravity = Gravity.CENTER;
         }
 
-        public void layout(SuggestedWords suggestedWords, ViewGroup stripView, ViewGroup placer,
-                int stripWidth) {
+        public void layout(final SuggestedWords suggestedWords, final ViewGroup stripView,
+                final ViewGroup placer, final int stripWidth) {
             if (suggestedWords.mIsPunctuationSuggestions) {
                 layoutPunctuationSuggestions(suggestedWords, stripView);
                 return;
@@ -402,7 +409,7 @@ public class SuggestionStripView extends RelativeLayout implements OnClickListen
                 x += word.getMeasuredWidth();
 
                 if (DBG && pos < suggestedWords.size()) {
-                    final CharSequence debugInfo = Utils.getDebugInfo(suggestedWords, pos);
+                    final String debugInfo = Utils.getDebugInfo(suggestedWords, pos);
                     if (debugInfo != null) {
                         final TextView info = mInfos.get(pos);
                         info.setText(debugInfo);
@@ -418,14 +425,14 @@ public class SuggestionStripView extends RelativeLayout implements OnClickListen
             }
         }
 
-        private int getSuggestionWidth(int index, int maxWidth) {
+        private int getSuggestionWidth(final int index, final int maxWidth) {
             final int paddings = mPadding * mSuggestionsCountInStrip;
             final int dividers = mDividerWidth * (mSuggestionsCountInStrip - 1);
             final int availableWidth = maxWidth - paddings - dividers;
             return (int)(availableWidth * getSuggestionWeight(index));
         }
 
-        private float getSuggestionWeight(int index) {
+        private float getSuggestionWeight(final int index) {
             if (index == mCenterSuggestionIndex) {
                 return mCenterSuggestionWeight;
             } else {
@@ -434,7 +441,7 @@ public class SuggestionStripView extends RelativeLayout implements OnClickListen
             }
         }
 
-        private void setupTexts(SuggestedWords suggestedWords, int countInStrip) {
+        private void setupTexts(final SuggestedWords suggestedWords, final int countInStrip) {
             mTexts.clear();
             final int count = Math.min(suggestedWords.size(), countInStrip);
             for (int pos = 0; pos < count; pos++) {
@@ -447,8 +454,8 @@ public class SuggestionStripView extends RelativeLayout implements OnClickListen
             }
         }
 
-        private void layoutPunctuationSuggestions(SuggestedWords suggestedWords,
-                ViewGroup stripView) {
+        private void layoutPunctuationSuggestions(final SuggestedWords suggestedWords,
+                final ViewGroup stripView) {
             final int countInStrip = Math.min(suggestedWords.size(), PUNCTUATIONS_IN_STRIP);
             for (int index = 0; index < countInStrip; index++) {
                 if (index != 0) {
@@ -459,7 +466,7 @@ public class SuggestionStripView extends RelativeLayout implements OnClickListen
                 final TextView word = mWords.get(index);
                 word.setEnabled(true);
                 word.setTextColor(mColorAutoCorrect);
-                final CharSequence text = suggestedWords.getWord(index);
+                final String text = suggestedWords.getWord(index);
                 word.setText(text);
                 word.setTextScaleX(1.0f);
                 word.setCompoundDrawables(null, null, null, null);
@@ -469,8 +476,8 @@ public class SuggestionStripView extends RelativeLayout implements OnClickListen
             mMoreSuggestionsAvailable = false;
         }
 
-        public void layoutAddToDictionaryHint(CharSequence word, ViewGroup stripView,
-                int stripWidth, CharSequence hintText, OnClickListener listener) {
+        public void layoutAddToDictionaryHint(final String word, final ViewGroup stripView,
+                final int stripWidth, final CharSequence hintText, final OnClickListener listener) {
             final int width = stripWidth - mDividerWidth - mPadding * 2;
 
             final TextView wordView = mWordToSaveView;
@@ -511,11 +518,11 @@ public class SuggestionStripView extends RelativeLayout implements OnClickListen
             return (CharSequence)mWordToSaveView.getTag();
         }
 
-        public boolean isAddToDictionaryShowing(View v) {
+        public boolean isAddToDictionaryShowing(final View v) {
             return v == mWordToSaveView || v == mHintToSaveView || v == mLeftwardsArrowView;
         }
 
-        private static void setLayoutWeight(View v, float weight, int height) {
+        private static void setLayoutWeight(final View v, final float weight, final int height) {
             final ViewGroup.LayoutParams lp = v.getLayoutParams();
             if (lp instanceof LinearLayout.LayoutParams) {
                 final LinearLayout.LayoutParams llp = (LinearLayout.LayoutParams)lp;
@@ -525,7 +532,8 @@ public class SuggestionStripView extends RelativeLayout implements OnClickListen
             }
         }
 
-        private static float getTextScaleX(CharSequence text, int maxWidth, TextPaint paint) {
+        private static float getTextScaleX(final CharSequence text, final int maxWidth,
+                final TextPaint paint) {
             paint.setTextScaleX(1.0f);
             final int width = getTextWidth(text, paint);
             if (width <= maxWidth) {
@@ -534,8 +542,8 @@ public class SuggestionStripView extends RelativeLayout implements OnClickListen
             return maxWidth / (float)width;
         }
 
-        private static CharSequence getEllipsizedText(CharSequence text, int maxWidth,
-                TextPaint paint) {
+        private static CharSequence getEllipsizedText(final CharSequence text, final int maxWidth,
+                final TextPaint paint) {
             if (text == null) return null;
             paint.setTextScaleX(1.0f);
             final int width = getTextWidth(text, paint);
@@ -556,7 +564,7 @@ public class SuggestionStripView extends RelativeLayout implements OnClickListen
             return ellipsized;
         }
 
-        private static int getTextWidth(CharSequence text, TextPaint paint) {
+        private static int getTextWidth(final CharSequence text, final TextPaint paint) {
             if (TextUtils.isEmpty(text)) return 0;
             final Typeface savedTypeface = paint.getTypeface();
             paint.setTypeface(getTextTypeface(text));
@@ -571,7 +579,7 @@ public class SuggestionStripView extends RelativeLayout implements OnClickListen
             return width;
         }
 
-        private static Typeface getTextTypeface(CharSequence text) {
+        private static Typeface getTextTypeface(final CharSequence text) {
             if (!(text instanceof SpannableString))
                 return Typeface.DEFAULT;
 
@@ -593,11 +601,12 @@ public class SuggestionStripView extends RelativeLayout implements OnClickListen
      * @param context
      * @param attrs
      */
-    public SuggestionStripView(Context context, AttributeSet attrs) {
+    public SuggestionStripView(final Context context, final AttributeSet attrs) {
         this(context, attrs, R.attr.suggestionStripViewStyle);
     }
 
-    public SuggestionStripView(Context context, AttributeSet attrs, int defStyle) {
+    public SuggestionStripView(final Context context, final AttributeSet attrs,
+            final int defStyle) {
         super(context, attrs, defStyle);
 
         final LayoutInflater inflater = LayoutInflater.from(context);
@@ -658,15 +667,12 @@ public class SuggestionStripView extends RelativeLayout implements OnClickListen
      * A connection back to the input method.
      * @param listener
      */
-    public void setListener(Listener listener, View inputView) {
+    public void setListener(final Listener listener, final View inputView) {
         mListener = listener;
         mKeyboardView = (KeyboardView)inputView.findViewById(R.id.keyboard_view);
     }
 
-    public void setSuggestions(SuggestedWords suggestedWords) {
-        if (suggestedWords == null)
-            return;
-
+    public void setSuggestions(final SuggestedWords suggestedWords) {
         clear();
         mSuggestedWords = suggestedWords;
         mParams.layout(mSuggestedWords, mSuggestionsStrip, this, getWidth());
@@ -675,7 +681,7 @@ public class SuggestionStripView extends RelativeLayout implements OnClickListen
         }
     }
 
-    public int setMoreSuggestionsHeight(int remainingHeight) {
+    public int setMoreSuggestionsHeight(final int remainingHeight) {
         return mParams.setMoreSuggestionsHeight(remainingHeight);
     }
 
@@ -684,7 +690,7 @@ public class SuggestionStripView extends RelativeLayout implements OnClickListen
                 && mParams.isAddToDictionaryShowing(mSuggestionsStrip.getChildAt(0));
     }
 
-    public void showAddToDictionaryHint(CharSequence word, CharSequence hintText) {
+    public void showAddToDictionaryHint(final String word, final CharSequence hintText) {
         clear();
         mParams.layoutAddToDictionaryHint(word, mSuggestionsStrip, getWidth(), hintText, this);
     }
@@ -708,16 +714,16 @@ public class SuggestionStripView extends RelativeLayout implements OnClickListen
         dismissMoreSuggestions();
     }
 
-    private void hidePreview() {
+    void hidePreview() {
         mPreviewPopup.dismiss();
     }
 
     private final KeyboardActionListener mMoreSuggestionsListener =
             new KeyboardActionListener.Adapter() {
         @Override
-        public boolean onCustomRequest(int requestCode) {
+        public boolean onCustomRequest(final int requestCode) {
             final int index = requestCode;
-            final CharSequence word = mSuggestedWords.getWord(index);
+            final String word = mSuggestedWords.getWord(index);
             mListener.pickSuggestionManually(index, word);
             dismissMoreSuggestions();
             return true;
@@ -737,7 +743,7 @@ public class SuggestionStripView extends RelativeLayout implements OnClickListen
         }
     };
 
-    private boolean dismissMoreSuggestions() {
+    boolean dismissMoreSuggestions() {
         if (mMoreSuggestionsWindow.isShowing()) {
             mMoreSuggestionsWindow.dismiss();
             return true;
@@ -746,41 +752,43 @@ public class SuggestionStripView extends RelativeLayout implements OnClickListen
     }
 
     @Override
-    public boolean onLongClick(View view) {
+    public boolean onLongClick(final View view) {
+        KeyboardSwitcher.getInstance().hapticAndAudioFeedback(Constants.NOT_A_CODE);
         return showMoreSuggestions();
     }
 
-    private boolean showMoreSuggestions() {
+    boolean showMoreSuggestions() {
+        final Keyboard parentKeyboard = KeyboardSwitcher.getInstance().getKeyboard();
+        if (parentKeyboard == null) {
+            return false;
+        }
         final SuggestionStripViewParams params = mParams;
-        if (params.mMoreSuggestionsAvailable) {
-            final int stripWidth = getWidth();
-            final View container = mMoreSuggestionsContainer;
-            final int maxWidth = stripWidth - container.getPaddingLeft()
-                    - container.getPaddingRight();
-            final MoreSuggestions.Builder builder = mMoreSuggestionsBuilder;
-            builder.layout(mSuggestedWords, params.mSuggestionsCountInStrip, maxWidth,
-                    (int)(maxWidth * params.mMinMoreSuggestionsWidth),
-                    params.getMaxMoreSuggestionsRow());
-            mMoreSuggestionsView.setKeyboard(builder.build());
-            container.measure(
-                    ViewGroup.LayoutParams.WRAP_CONTENT, ViewGroup.LayoutParams.WRAP_CONTENT);
-
-            final MoreKeysPanel moreKeysPanel = mMoreSuggestionsView;
-            final int pointX = stripWidth / 2;
-            final int pointY = -params.mMoreSuggestionsBottomGap;
-            moreKeysPanel.showMoreKeysPanel(
-                    this, mMoreSuggestionsController, pointX, pointY,
-                    mMoreSuggestionsWindow, mMoreSuggestionsListener);
-            mMoreSuggestionsMode = MORE_SUGGESTIONS_CHECKING_MODAL_OR_SLIDING;
-            mOriginX = mLastX;
-            mOriginY = mLastY;
-            mKeyboardView.dimEntireKeyboard(true);
-            for (int i = 0; i < params.mSuggestionsCountInStrip; i++) {
-                mWords.get(i).setPressed(false);
-            }
-            return true;
+        if (!params.mMoreSuggestionsAvailable) {
+            return false;
         }
-        return false;
+        final int stripWidth = getWidth();
+        final View container = mMoreSuggestionsContainer;
+        final int maxWidth = stripWidth - container.getPaddingLeft() - container.getPaddingRight();
+        final MoreSuggestions.Builder builder = mMoreSuggestionsBuilder;
+        builder.layout(mSuggestedWords, params.mSuggestionsCountInStrip, maxWidth,
+                (int)(maxWidth * params.mMinMoreSuggestionsWidth),
+                params.getMaxMoreSuggestionsRow(), parentKeyboard);
+        mMoreSuggestionsView.setKeyboard(builder.build());
+        container.measure(ViewGroup.LayoutParams.WRAP_CONTENT, ViewGroup.LayoutParams.WRAP_CONTENT);
+
+        final MoreKeysPanel moreKeysPanel = mMoreSuggestionsView;
+        final int pointX = stripWidth / 2;
+        final int pointY = -params.mMoreSuggestionsBottomGap;
+        moreKeysPanel.showMoreKeysPanel(this, mMoreSuggestionsController, pointX, pointY,
+                mMoreSuggestionsWindow, mMoreSuggestionsListener);
+        mMoreSuggestionsMode = MORE_SUGGESTIONS_CHECKING_MODAL_OR_SLIDING;
+        mOriginX = mLastX;
+        mOriginY = mLastY;
+        mKeyboardView.dimEntireKeyboard(true);
+        for (int i = 0; i < params.mSuggestionsCountInStrip; i++) {
+            mWords.get(i).setPressed(false);
+        }
+        return true;
     }
 
     // Working variables for onLongClick and dispatchTouchEvent.
@@ -807,7 +815,7 @@ public class SuggestionStripView extends RelativeLayout implements OnClickListen
     };
 
     @Override
-    public boolean dispatchTouchEvent(MotionEvent me) {
+    public boolean dispatchTouchEvent(final MotionEvent me) {
         if (!mMoreSuggestionsWindow.isShowing()
                 || mMoreSuggestionsMode == MORE_SUGGESTIONS_IN_MODAL_MODE) {
             mLastX = (int)me.getX();
@@ -849,7 +857,7 @@ public class SuggestionStripView extends RelativeLayout implements OnClickListen
     }
 
     @Override
-    public void onClick(View view) {
+    public void onClick(final View view) {
         if (mParams.isAddToDictionaryShowing(view)) {
             mListener.addWordToUserDictionary(mParams.getAddToDictionaryWord().toString());
             clear();
@@ -863,7 +871,7 @@ public class SuggestionStripView extends RelativeLayout implements OnClickListen
         if (index >= mSuggestedWords.size())
             return;
 
-        final CharSequence word = mSuggestedWords.getWord(index);
+        final String word = mSuggestedWords.getWord(index);
         mListener.pickSuggestionManually(index, word);
     }
author	Satoshi Kataoka <satok@google.com>	2012-11-06 12:49:53 +0900
committer	Satoshi Kataoka <satok@google.com>	2012-11-06 12:49:53 +0900
commit	555e15a96a00e8829981557d96e9fa7fc5a74f8c (patch)
tree	9750c7af9777b63c176cc780c2a6de4849931434 /java/src/com/android/inputmethod/latin
parent	9381ab669f12664f7e2debea846d3ce71f89b256 (diff)
parent	5f2fa6b82cbb6714ab2996aebc16f10c62d0e673 (diff)
download	latinime-555e15a96a00e8829981557d96e9fa7fc5a74f8c.tar.gz latinime-555e15a96a00e8829981557d96e9fa7fc5a74f8c.tar.xz latinime-555e15a96a00e8829981557d96e9fa7fc5a74f8c.zip