Rename the user history dictionary.

UserBigramDictionary -> UserHistoryDictionary.

Also update all methods, strings and comments, except those needed
for backward compatibility (which only include the name of the
database file).

Change-Id: I0bccea29880dc566b90100575b83baaa947b03ae

1 files changed, 0 insertions, 469 deletions

diff --git a/java/src/com/android/inputmethod/latin/UserBigramDictionary.java b/java/src/com/android/inputmethod/latin/UserBigramDictionary.java
deleted file mode 100644
index 91f84bed1..000000000
--- a/java/src/com/android/inputmethod/latin/UserBigramDictionary.java
+++ /dev/null
@@ -1,469 +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;
-
-import android.content.ContentValues;
-import android.content.Context;
-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.text.TextUtils;
-import android.util.Log;
-
-import java.util.HashMap;
-import java.util.HashSet;
-import java.util.Iterator;
-
-/**
- * Stores all the pairs user types in databases. Prune the database if the size
- * gets too big. Unlike AutoDictionary, it even stores the pairs that are already
- * in the dictionary.
- */
-public class UserBigramDictionary extends ExpandableDictionary {
-    private static final String TAG = "UserBigramDictionary";
-
-    /** Any pair being typed or picked */
-    private static final int FREQUENCY_FOR_TYPED = 2;
-
-    /** Maximum frequency for all pairs */
-    private static final int FREQUENCY_MAX = 127;
-
-    /** Maximum number of pairs. Pruning will start when databases goes above this number. */
-    private static int sMaxUserBigrams = 10000;
-
-    /**
-     * When it hits maximum bigram pair, it will delete until you are left with
-     * only (sMaxUserBigrams - sDeleteUserBigrams) pairs.
-     * Do not keep this number small to avoid deleting too often.
-     */
-    private static int sDeleteUserBigrams = 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. (Same TODO from AutoDictionary)
-    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 FREQ_COLUMN_FREQUENCY = "freq";
-
-    private final LatinIME mIme;
-
-    /** Locale for which this auto dictionary is storing words */
-    private String mLocale;
-
-    private HashSet<Bigram> mPendingWrites = new HashSet<Bigram>();
-    private final Object mPendingWritesLock = new Object();
-    private static volatile boolean sUpdatingDB = false;
-
-    private final static HashMap<String, String> sDictProjectionMap;
-
-    static {
-        sDictProjectionMap = new HashMap<String, String>();
-        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(FREQ_COLUMN_FREQUENCY, FREQ_COLUMN_FREQUENCY);
-    }
-
-    private static DatabaseHelper sOpenHelper = null;
-
-    private static class Bigram {
-        public final String mWord1;
-        public final String mWord2;
-        public final int mFrequency;
-
-        Bigram(String word1, String word2, int frequency) {
-            this.mWord1 = word1;
-            this.mWord2 = word2;
-            this.mFrequency = frequency;
-        }
-
-        @Override
-        public boolean equals(Object bigram) {
-            if (!(bigram instanceof Bigram)) {
-                return false;
-            }
-            final Bigram bigram2 = (Bigram) bigram;
-            final boolean eq1 =
-                    mWord1 == null ? bigram2.mWord1 == null : mWord1.equals(bigram2.mWord1);
-            if (!eq1) {
-                return false;
-            }
-            return mWord2 == null ? bigram2.mWord2 == null : mWord2.equals(bigram2.mWord2);
-        }
-
-        @Override
-        public int hashCode() {
-            return (mWord1 + " " + mWord2).hashCode();
-        }
-    }
-
-    public void setDatabaseMax(int maxUserBigram) {
-        sMaxUserBigrams = maxUserBigram;
-    }
-
-    public void setDatabaseDelete(int deleteUserBigram) {
-        sDeleteUserBigrams = deleteUserBigram;
-    }
-
-    public UserBigramDictionary(Context context, LatinIME ime, String locale, int dicTypeId) {
-        super(context, dicTypeId);
-        mIme = ime;
-        mLocale = locale;
-        if (sOpenHelper == null) {
-            sOpenHelper = new DatabaseHelper(getContext());
-        }
-        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();
-        super.close();
-    }
-
-    /**
-     * Return whether the passed charsequence is in the dictionary.
-     */
-    @Override
-    public boolean isValidWord(final CharSequence word) {
-        // TODO: figure out what is the correct thing to do here.
-        return false;
-    }
-
-    /**
-     * Add a single word without context.
-     *
-     * This is a temporary method to match the interface to UserUnigramDictionary. In the end
-     * this should be merged with addBigramPair.
-     */
-    public void addUnigram(final String newWord) {
-        addBigramPair(null, newWord);
-    }
-
-    /**
-     * 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 addBigramPair(final String word1, String word2) {
-        // remove caps if second word is autocapitalized
-        if (mIme != null && mIme.isAutoCapitalized()) {
-            word2 = Character.toLowerCase(word2.charAt(0)) + word2.substring(1);
-        }
-        // Do not insert a word as a bigram of itself
-        if (word2.equals(word1)) {
-            return 0;
-        }
-
-        int freq;
-        if (null == word1) {
-            freq = FREQUENCY_FOR_TYPED;
-            super.addWord(word2, FREQUENCY_FOR_TYPED);
-        } else {
-            freq = super.addBigram(word1, word2, FREQUENCY_FOR_TYPED);
-        }
-        if (freq > FREQUENCY_MAX) freq = FREQUENCY_MAX;
-        synchronized (mPendingWritesLock) {
-            if (freq == FREQUENCY_FOR_TYPED || mPendingWrites.isEmpty()) {
-                mPendingWrites.add(new Bigram(word1, word2, freq));
-            } else {
-                Bigram bi = new Bigram(word1, word2, freq);
-                mPendingWrites.remove(bi);
-                mPendingWrites.add(bi);
-            }
-        }
-
-        return freq;
-    }
-
-    /**
-     * Schedules a background thread to write any pending words to the database.
-     */
-    public void flushPendingWrites() {
-        synchronized (mPendingWritesLock) {
-            // Nothing pending? Return
-            if (mPendingWrites.isEmpty()) return;
-            // Create a background thread to write the pending entries
-            new UpdateDbTask(sOpenHelper, mPendingWrites, mLocale).execute();
-            // Create a new map for writing new entries into while the old one is written to db
-            mPendingWrites = new HashSet<Bigram>();
-        }
-    }
-
-    /** Used for testing purpose **/
-    void waitUntilUpdateDBDone() {
-        synchronized (mPendingWritesLock) {
-            while (sUpdatingDB) {
-                try {
-                    Thread.sleep(100);
-                } catch (InterruptedException e) {
-                }
-            }
-            return;
-        }
-    }
-
-    @Override
-    public void loadDictionaryAsync() {
-        // 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 {
-            if (cursor.moveToFirst()) {
-                int word1Index = cursor.getColumnIndex(MAIN_COLUMN_WORD1);
-                int word2Index = cursor.getColumnIndex(MAIN_COLUMN_WORD2);
-                int frequencyIndex = cursor.getColumnIndex(FREQ_COLUMN_FREQUENCY);
-                while (!cursor.isAfterLast()) {
-                    String word1 = cursor.getString(word1Index);
-                    String word2 = cursor.getString(word2Index);
-                    int frequency = cursor.getInt(frequencyIndex);
-                    // Safeguard against adding really long words. Stack may overflow due
-                    // to recursive lookup
-                    if (null == word1) {
-                        super.addWord(word2, frequency);
-                    } else if (word1.length() < MAX_WORD_LENGTH
-                            && word2.length() < MAX_WORD_LENGTH) {
-                        super.setBigram(word1, word2, frequency);
-                    }
-                    cursor.moveToNext();
-                }
-            }
-        } finally {
-            cursor.close();
-        }
-    }
-
-    /**
-     * 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, FREQ_COLUMN_FREQUENCY },
-                    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,"
-                    + FREQ_COLUMN_FREQUENCY + " 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.
-     */
-    private static class UpdateDbTask extends AsyncTask<Void, Void, Void> {
-        private final HashSet<Bigram> mMap;
-        private final DatabaseHelper mDbHelper;
-        private final String mLocale;
-
-        public UpdateDbTask(DatabaseHelper openHelper, HashSet<Bigram> pendingWrites,
-                String locale) {
-            mMap = pendingWrites;
-            mLocale = locale;
-            mDbHelper = openHelper;
-        }
-
-        /** 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 > sMaxUserBigrams) {
-                    int numDeleteRows = (totalRowCount - sMaxUserBigrams) + sDeleteUserBigrams;
-                    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();
-            }
-        }
-
-        @Override
-        protected void onPreExecute() {
-            sUpdatingDB = true;
-        }
-
-        @Override
-        protected Void doInBackground(Void... v) {
-            SQLiteDatabase db = null;
-            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.
-                sUpdatingDB = false;
-                return null;
-            }
-            db.execSQL("PRAGMA foreign_keys = ON;");
-            // Write all the entries to the db
-            Iterator<Bigram> iterator = mMap.iterator();
-            while (iterator.hasNext()) {
-                // TODO: this process of making a text search for each pair each time
-                // is terribly inefficient. Optimize this.
-                Bigram bi = iterator.next();
-
-                // find pair id
-                final Cursor c;
-                if (null != bi.mWord1) {
-                    c = db.query(MAIN_TABLE_NAME, new String[] { MAIN_COLUMN_ID },
-                            MAIN_COLUMN_WORD1 + "=? AND " + MAIN_COLUMN_WORD2 + "=? AND "
-                            + MAIN_COLUMN_LOCALE + "=?",
-                            new String[] { bi.mWord1, bi.mWord2, 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[] { bi.mWord2, mLocale }, null, null, null);
-                }
-
-                int pairId;
-                if (c.moveToFirst()) {
-                    // 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 {
-                    // new pair
-                    Long pairIdLong = db.insert(MAIN_TABLE_NAME, null,
-                            getContentValues(bi.mWord1, bi.mWord2, mLocale));
-                    pairId = pairIdLong.intValue();
-                }
-                c.close();
-
-                // insert new frequency
-                db.insert(FREQ_TABLE_NAME, null, getFrequencyContentValues(pairId, bi.mFrequency));
-            }
-            checkPruneData(db);
-            sUpdatingDB = false;
-
-            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;
-        }
-
-        private static ContentValues getFrequencyContentValues(int pairId, int frequency) {
-           ContentValues values = new ContentValues(2);
-           values.put(FREQ_COLUMN_PAIR_ID, pairId);
-           values.put(FREQ_COLUMN_FREQUENCY, frequency);
-           return values;
-        }
-    }
-
-}