Refactor on the user history dictionary

Bug: 9429906
Bug: 4192129
Change-Id: I1a2bfe96e18119d30a72290aa48746f77a021018

1 files changed, 0 insertions, 397 deletions

diff --git a/java/src/com/android/inputmethod/latin/personalization/UserHistoryDictionary.java b/java/src/com/android/inputmethod/latin/personalization/UserHistoryDictionary.java
deleted file mode 100644
index c76dea0bb..000000000
--- a/java/src/com/android/inputmethod/latin/personalization/UserHistoryDictionary.java
+++ /dev/null
@@ -1,397 +0,0 @@
-/*
- * Copyright (C) 2010 The Android Open Source Project
- *
- * 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.personalization;
-
-import android.content.Context;
-import android.content.SharedPreferences;
-import android.os.AsyncTask;
-import android.util.Log;
-
-import com.android.inputmethod.annotations.UsedForTesting;
-import com.android.inputmethod.keyboard.ProximityInfo;
-import com.android.inputmethod.latin.Constants;
-import com.android.inputmethod.latin.Dictionary;
-import com.android.inputmethod.latin.ExpandableDictionary;
-import com.android.inputmethod.latin.LatinImeLogger;
-import com.android.inputmethod.latin.SuggestedWords.SuggestedWordInfo;
-import com.android.inputmethod.latin.WordComposer;
-import com.android.inputmethod.latin.makedict.FormatSpec.FormatOptions;
-import com.android.inputmethod.latin.settings.Settings;
-import com.android.inputmethod.latin.utils.ByteArrayWrapper;
-import com.android.inputmethod.latin.utils.UserHistoryDictIOUtils;
-import com.android.inputmethod.latin.utils.UserHistoryDictIOUtils.BigramDictionaryInterface;
-import com.android.inputmethod.latin.utils.UserHistoryDictIOUtils.OnAddWordListener;
-import com.android.inputmethod.latin.utils.UserHistoryForgettingCurveUtils;
-import com.android.inputmethod.latin.utils.UserHistoryForgettingCurveUtils.ForgettingCurveParams;
-
-import java.io.File;
-import java.io.FileInputStream;
-import java.io.FileNotFoundException;
-import java.io.FileOutputStream;
-import java.io.IOException;
-import java.util.ArrayList;
-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.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 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 DELETE_HISTORY_BIGRAMS = 1000;
-
-    /** Locale for which this user history dictionary is storing words */
-    private final String mLocale;
-
-    private final UserHistoryDictionaryBigramList mBigramList =
-            new UserHistoryDictionaryBigramList();
-    private final ReentrantLock mBigramListLock = new ReentrantLock();
-    private final SharedPreferences mPrefs;
-
-    // Should always be false except when we use this class for test
-    @UsedForTesting boolean isTest = false;
-
-    /* package */ UserHistoryDictionary(final Context context, final String locale,
-            final SharedPreferences sp) {
-        super(context, Dictionary.TYPE_USER_HISTORY);
-        mLocale = locale;
-        mPrefs = sp;
-        if (mLocale != null && mLocale.length() > 1) {
-            loadDictionary();
-        }
-    }
-
-    @Override
-    public void close() {
-        flushPendingWrites();
-        // Don't close the database as locale changes will require it to be reopened anyway
-        // Also, the database is written to somewhat frequently, so it needs to be kept alive
-        // throughout the life of the process.
-        // mOpenHelper.close();
-        // Ignore close because we cache UserHistoryDictionary for each language. See getInstance()
-        // above.
-        // super.close();
-    }
-
-    @Override
-    protected ArrayList<SuggestedWordInfo> getWordsInner(final WordComposer composer,
-            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;
-    }
-
-    /**
-     * Return whether the passed charsequence is in the dictionary.
-     */
-    @Override
-    public synchronized boolean isValidWord(final String word) {
-        // TODO: figure out what is the correct thing to do here.
-        return false;
-    }
-
-    /**
-     * Pair will be added to the user history dictionary.
-     *
-     * The first word may be null. That means we don't know the context, in other words,
-     * it's only a unigram. The first word may also be an empty string : this means start
-     * 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, final String word2, final boolean isValid) {
-        if (word2.length() >= Constants.DICTIONARY_MAX_WORD_LENGTH ||
-                (word1 != null && word1.length() >= Constants.DICTIONARY_MAX_WORD_LENGTH)) {
-            return -1;
-        }
-        if (mBigramListLock.tryLock()) {
-            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;
-                }
-                final int freq;
-                if (null == word1) {
-                    freq = FREQUENCY_FOR_TYPED;
-                } else {
-                    freq = super.setBigramAndGetFrequency(
-                            word1, word2, new ForgettingCurveParams(isValid));
-                }
-                mBigramList.addBigram(word1, word2);
-                return freq;
-            } finally {
-                mBigramListLock.unlock();
-            }
-        }
-        return -1;
-    }
-
-    public boolean cancelAddingUserHistory(final String word1, final String word2) {
-        if (mBigramListLock.tryLock()) {
-            try {
-                if (mBigramList.removeBigram(word1, word2)) {
-                    return super.removeBigram(word1, word2);
-                }
-            } finally {
-                mBigramListLock.unlock();
-            }
-        }
-        return false;
-    }
-
-    /**
-     * Schedules a background thread to write any pending words to the database.
-     */
-    private void flushPendingWrites() {
-        // Create a background thread to write the pending entries
-        new UpdateBinaryTask(mBigramList, mLocale, this, mPrefs, getContext()).execute();
-    }
-
-    @Override
-    public void loadDictionaryAsync() {
-        // This must be run on non-main thread
-        mBigramListLock.lock();
-        try {
-            loadDictionaryAsyncLocked();
-        } finally {
-            mBigramListLock.unlock();
-        }
-    }
-
-    private int profTotal;
-
-    private void loadDictionaryAsyncLocked() {
-        if (DBG_STRESS_TEST) {
-            try {
-                Log.w(TAG, "Start stress in loading: " + mLocale);
-                Thread.sleep(15000);
-                Log.w(TAG, "End stress in loading");
-            } catch (InterruptedException e) {
-            }
-        }
-        final long last = Settings.readLastUserHistoryWriteTime(mPrefs, mLocale);
-        final boolean initializing = last == 0;
-        final long now = System.currentTimeMillis();
-        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() < Constants.DICTIONARY_MAX_WORD_LENGTH
-                        && word2.length() < Constants.DICTIONARY_MAX_WORD_LENGTH) {
-                    profTotal++;
-                    if (DBG_SAVE_RESTORE) {
-                        Log.d(TAG, "load bigram: " + word1 + "," + word2 + "," + frequency);
-                    }
-                    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 ByteArrayWrapper(buffer), listener);
-        } catch (FileNotFoundException e) {
-            // This is an expected condition: we don't have a user history dictionary for this
-            // language yet. It will be created sometime later.
-        } catch (IOException e) {
-            Log.e(TAG, "IOException on opening a bytebuffer", e);
-        } finally {
-            if (inStream != null) {
-                try {
-                    inStream.close();
-                } catch (IOException e) {
-                    // do nothing
-                }
-            }
-            if (PROFILE_SAVE_RESTORE) {
-                final long diff = System.currentTimeMillis() - now;
-                Log.d(TAG, "PROF: Load UserHistoryDictionary: "
-                        + mLocale + ", " + diff + "ms. load " + profTotal + "entries.");
-            }
-        }
-    }
-
-    /**
-     * Async task to write pending words to the binarydicts.
-     */
-    private static final class UpdateBinaryTask extends AsyncTask<Void, Void, Void>
-            implements BigramDictionaryInterface {
-        private final UserHistoryDictionaryBigramList mBigramList;
-        private final boolean mAddLevel0Bigrams;
-        private final String mLocale;
-        private final UserHistoryDictionary mUserHistoryDictionary;
-        private final SharedPreferences mPrefs;
-        private final Context mContext;
-
-        public UpdateBinaryTask(final UserHistoryDictionaryBigramList pendingWrites,
-                final String locale, final UserHistoryDictionary dict,
-                final SharedPreferences prefs, final Context context) {
-            mBigramList = pendingWrites;
-            mLocale = locale;
-            mUserHistoryDictionary = dict;
-            mPrefs = prefs;
-            mContext = context;
-            mAddLevel0Bigrams = mBigramList.size() <= MAX_HISTORY_BIGRAMS;
-        }
-
-        @Override
-        protected Void doInBackground(final Void... v) {
-            if (mUserHistoryDictionary.isTest) {
-                // If isTest == true, wait until the lock is released.
-                mUserHistoryDictionary.mBigramListLock.lock();
-                try {
-                    doWriteTaskLocked();
-                } finally {
-                    mUserHistoryDictionary.mBigramListLock.unlock();
-                }
-            } else if (mUserHistoryDictionary.mBigramListLock.tryLock()) {
-                try {
-                    doWriteTaskLocked();
-                } finally {
-                    mUserHistoryDictionary.mBigramListLock.unlock();
-                }
-            }
-            return null;
-        }
-
-        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;
-            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 {
-                        out.close();
-                    } catch (IOException e) {
-                        // ignore
-                    }
-                }
-            }
-
-            // Save the timestamp after we finish writing the binary dictionary.
-            Settings.writeLastUserHistoryWriteTime(mPrefs, mLocale);
-            if (PROFILE_SAVE_RESTORE) {
-                final long diff = System.currentTimeMillis() - now;
-                Log.w(TAG, "PROF: Write User HistoryDictionary: " + mLocale + ", " + diff + "ms.");
-            }
-        }
-
-        @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 = fc & 0xFF;
-                    } else if (UserHistoryForgettingCurveUtils.
-                            needsToSave(fc, isValid, mAddLevel0Bigrams)) {
-                        freq = fc & 0xFF;
-                    } else {
-                        // Delete this entry
-                        freq = -1;
-                    }
-                } else {
-                    // Delete this entry
-                    freq = -1;
-                }
-            }
-            return freq;
-        }
-    }
-
-    @UsedForTesting
-    /* package for test */ void forceAddWordForTest(
-            final String word1, final String word2, final boolean isValid) {
-        mBigramListLock.lock();
-        try {
-            addToUserHistory(word1, word2, isValid);
-        } finally {
-            mBigramListLock.unlock();
-        }
-    }
-}