1 files changed, 151 insertions, 0 deletions
diff --git a/java/src/com/android/inputmethod/latin/BinaryDictionary.java b/java/src/com/android/inputmethod/latin/BinaryDictionary.java
new file mode 100644
index 000000000..43f4c4cb6
--- /dev/null
+++ b/java/src/com/android/inputmethod/latin/BinaryDictionary.java
@@ -0,0 +1,151 @@
+/*
+ * Copyright (C) 2008-2009 Google Inc.
+ * 
+ * Licensed under the Apache License, Version 2.0 (the "License"); you may not
+ * use this file except in compliance with the License. You may obtain a copy of
+ * the License at
+ * 
+ * http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+ * License for the specific language governing permissions and limitations under
+ * the License.
+ */
+
+package com.android.inputmethod.latin;
+
+import java.util.Arrays;
+
+import android.content.Context;
+import android.content.res.AssetManager;
+import android.util.Log;
+
+/**
+ * Implements a static, compacted, binary dictionary of standard words.
+ */
+public class BinaryDictionary extends Dictionary {
+
+    public static final int MAX_WORD_LENGTH = 48;
+    private static final int MAX_ALTERNATIVES = 16;
+    private static final int MAX_WORDS = 16;
+
+    private static final int TYPED_LETTER_MULTIPLIER = 2;
+    private static final boolean ENABLE_MISSED_CHARACTERS = true;
+
+    private int mNativeDict;
+    private int mDictLength; // This value is set from native code, don't change the name!!!!
+    private int[] mInputCodes = new int[MAX_WORD_LENGTH * MAX_ALTERNATIVES];
+    private char[] mOutputChars = new char[MAX_WORD_LENGTH * MAX_WORDS];
+    private int[] mFrequencies = new int[MAX_WORDS];
+
+    static {
+        try {
+            System.loadLibrary("jni_latinime");
+        } catch (UnsatisfiedLinkError ule) {
+            Log.e("BinaryDictionary", "Could not load native library jni_latinime");
+        }
+    }
+
+    /**
+     * Create a dictionary from a raw resource file
+     * @param context application context for reading resources
+     * @param resId the resource containing the raw binary dictionary
+     */
+    public BinaryDictionary(Context context, int resId) {
+        if (resId != 0) {
+            loadDictionary(context, resId);
+        }
+    }
+
+    private native int openNative(AssetManager am, String resourcePath, int typedLetterMultiplier,
+            int fullWordMultiplier);
+    private native void closeNative(int dict);
+    private native boolean isValidWordNative(int nativeData, char[] word, int wordLength);
+    private native int getSuggestionsNative(int dict, int[] inputCodes, int codesSize, 
+            char[] outputChars, int[] frequencies,
+            int maxWordLength, int maxWords, int maxAlternatives, int skipPos,
+            int[] nextLettersFrequencies, int nextLettersSize);
+
+    private final void loadDictionary(Context context, int resId) {
+        AssetManager am = context.getResources().getAssets();
+        String assetName = context.getResources().getString(resId);
+        mNativeDict = openNative(am, assetName, TYPED_LETTER_MULTIPLIER, FULL_WORD_FREQ_MULTIPLIER);
+    }
+
+    @Override
+    public void getWords(final WordComposer codes, final WordCallback callback,
+            int[] nextLettersFrequencies) {
+        final int codesSize = codes.size();
+        // Wont deal with really long words.
+        if (codesSize > MAX_WORD_LENGTH - 1) return;
+        
+        Arrays.fill(mInputCodes, -1);
+        for (int i = 0; i < codesSize; i++) {
+            int[] alternatives = codes.getCodesAt(i);
+            System.arraycopy(alternatives, 0, mInputCodes, i * MAX_ALTERNATIVES,
+                    Math.min(alternatives.length, MAX_ALTERNATIVES));
+        }
+        Arrays.fill(mOutputChars, (char) 0);
+        Arrays.fill(mFrequencies, 0);
+
+        int count = getSuggestionsNative(mNativeDict, mInputCodes, codesSize,
+                mOutputChars, mFrequencies,
+                MAX_WORD_LENGTH, MAX_WORDS, MAX_ALTERNATIVES, -1,
+                nextLettersFrequencies,
+                nextLettersFrequencies != null ? nextLettersFrequencies.length : 0);
+
+        // If there aren't sufficient suggestions, search for words by allowing wild cards at
+        // the different character positions. This feature is not ready for prime-time as we need
+        // to figure out the best ranking for such words compared to proximity corrections and
+        // completions.
+        if (ENABLE_MISSED_CHARACTERS && count < 5) {
+            for (int skip = 0; skip < codesSize; skip++) {
+                int tempCount = getSuggestionsNative(mNativeDict, mInputCodes, codesSize,
+                        mOutputChars, mFrequencies,
+                        MAX_WORD_LENGTH, MAX_WORDS, MAX_ALTERNATIVES, skip,
+                        null, 0);
+                count = Math.max(count, tempCount);
+                if (tempCount > 0) break;
+            }
+        }
+
+        for (int j = 0; j < count; j++) {
+            if (mFrequencies[j] < 1) break;
+            int start = j * MAX_WORD_LENGTH;
+            int len = 0;
+            while (mOutputChars[start + len] != 0) {
+                len++;
+            }
+            if (len > 0) {
+                callback.addWord(mOutputChars, start, len, mFrequencies[j]);
+            }
+        }
+    }
+
+    @Override
+    public boolean isValidWord(CharSequence word) {
+        if (word == null) return false;
+        char[] chars = word.toString().toCharArray();
+        return isValidWordNative(mNativeDict, chars, chars.length);
+    }
+
+    public int getSize() {
+        return mDictLength; // This value is initialized on the call to openNative()
+    }
+
+    @Override
+    public synchronized void close() {
+        if (mNativeDict != 0) {
+            closeNative(mNativeDict);
+            mNativeDict = 0;
+        }
+    }
+
+    @Override
+    protected void finalize() throws Throwable {
+        close();
+        super.finalize();
+    }
+}