LatinIME/java/src/com/android/inputmethod/latin/BinaryDictionary.java

244 lines
10 KiB
Java
Raw Normal View History

/*
* Copyright (C) 2008 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.Context;
import android.text.TextUtils;
import android.util.SparseArray;
import com.android.inputmethod.keyboard.ProximityInfo;
import com.android.inputmethod.latin.SuggestedWords.SuggestedWordInfo;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Locale;
/**
* Implements a static, compacted, binary dictionary of standard words.
*/
public class BinaryDictionary extends Dictionary {
public static final String DICTIONARY_PACK_AUTHORITY =
"com.android.inputmethod.latin.dictionarypack";
/**
* There is a difference between what java and native code can handle.
* This value should only be used in BinaryDictionary.java
* It is necessary to keep it at this value because some languages e.g. German have
* really long words.
*/
public static final int MAX_WORD_LENGTH = 48;
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[] mSpaceIndices = new int[MAX_SPACES];
private final int[] mOutputScores = new int[MAX_RESULTS];
private final int[] mOutputTypes = new int[MAX_RESULTS];
private final boolean mUseFullEditDistance;
private final SparseArray<DicTraverseSession> mDicTraverseSessions =
new SparseArray<DicTraverseSession>();
// TODO: There should be a way to remove used DicTraverseSession objects from
// {@code mDicTraverseSessions}.
private DicTraverseSession getTraverseSession(int traverseSessionId) {
synchronized(mDicTraverseSessions) {
DicTraverseSession traverseSession = mDicTraverseSessions.get(traverseSessionId);
if (traverseSession == null) {
traverseSession = mDicTraverseSessions.get(traverseSessionId);
if (traverseSession == null) {
traverseSession = new DicTraverseSession(mLocale, mNativeDict);
mDicTraverseSessions.put(traverseSessionId, traverseSession);
}
}
return traverseSession;
}
}
/**
* 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.
* @param length the length of the binary data.
* @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) {
super(dictType);
mLocale = locale;
mUseFullEditDistance = useFullEditDistance;
loadDictionary(filename, offset, length);
}
static {
JniUtils.loadNativeLibrary();
}
private native long openNative(String sourceDir, long dictOffset, long dictSize,
int typedLetterMultiplier, 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[] 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);
// 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);
}
@Override
public ArrayList<SuggestedWordInfo> getSuggestions(final WordComposer composer,
final CharSequence 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) {
if (!isValidDictionary()) return null;
Arrays.fill(mInputCodePoints, WordComposer.NOT_A_CODE);
// TODO: toLowerCase in the native code
final int[] prevWordCodePointArray = (null == prevWord)
? null : StringUtils.toCodePointArray(prevWord.toString());
final int composerSize = composer.size();
final boolean isGesture = composer.isBatchMode();
if (composerSize <= 1 || !isGesture) {
if (composerSize > MAX_WORD_LENGTH - 1) return null;
for (int i = 0; i < composerSize; i++) {
mInputCodePoints[i] = composer.getCodeAt(i);
}
}
final InputPointers ips = composer.getInputPointers();
final int codesSize = isGesture ? ips.getPointerSize() : composerSize;
// proximityInfo and/or prevWordForBigrams may not be null.
final int tmpCount = getSuggestionsNative(mNativeDict,
proximityInfo.getNativeProximityInfo(), getTraverseSession(sessionId).getSession(),
ips.getXCoordinates(), ips.getYCoordinates(), ips.getTimes(), ips.getPointerIds(),
mInputCodePoints, codesSize, 0 /* commitPoint */, isGesture, prevWordCodePointArray,
mUseFullEditDistance, mOutputChars, mOutputScores, mSpaceIndices, mOutputTypes);
final int count = Math.min(tmpCount, MAX_PREDICTIONS);
final ArrayList<SuggestedWordInfo> suggestions = new ArrayList<SuggestedWordInfo>();
for (int j = 0; j < count; ++j) {
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) {
++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));
}
}
return suggestions;
}
/* package for test */ boolean isValidDictionary() {
return mNativeDict != 0;
}
public static float calcNormalizedScore(String before, String after, int score) {
return calcNormalizedScoreNative(before.toCharArray(), after.toCharArray(), score);
}
public static int editDistance(String before, String after) {
return editDistanceNative(before.toCharArray(), after.toCharArray());
}
@Override
public boolean isValidWord(CharSequence word) {
return getFrequency(word) >= 0;
}
@Override
public int getFrequency(CharSequence word) {
if (word == null) return -1;
int[] codePoints = StringUtils.toCodePointArray(word.toString());
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) {
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);
}
@Override
public void close() {
synchronized (mDicTraverseSessions) {
final int sessionsSize = mDicTraverseSessions.size();
for (int index = 0; index < sessionsSize; ++index) {
final DicTraverseSession traverseSession = mDicTraverseSessions.valueAt(index);
if (traverseSession != null) {
traverseSession.close();
}
}
}
closeInternal();
}
private synchronized void closeInternal() {
if (mNativeDict != 0) {
closeNative(mNativeDict);
mNativeDict = 0;
}
}
@Override
protected void finalize() throws Throwable {
try {
closeInternal();
} finally {
super.finalize();
}
}
}