NgramContext.java revision 86f36003fd4397143bd37938dda029e5707634af
183c40a2301a0b5a42a75eecada48e7887a7c940eKeisuke Kuroyanagi/* 283c40a2301a0b5a42a75eecada48e7887a7c940eKeisuke Kuroyanagi * Copyright (C) 2014 The Android Open Source Project 383c40a2301a0b5a42a75eecada48e7887a7c940eKeisuke Kuroyanagi * 483c40a2301a0b5a42a75eecada48e7887a7c940eKeisuke Kuroyanagi * Licensed under the Apache License, Version 2.0 (the "License"); 583c40a2301a0b5a42a75eecada48e7887a7c940eKeisuke Kuroyanagi * you may not use this file except in compliance with the License. 683c40a2301a0b5a42a75eecada48e7887a7c940eKeisuke Kuroyanagi * You may obtain a copy of the License at 783c40a2301a0b5a42a75eecada48e7887a7c940eKeisuke Kuroyanagi * 883c40a2301a0b5a42a75eecada48e7887a7c940eKeisuke Kuroyanagi * http://www.apache.org/licenses/LICENSE-2.0 983c40a2301a0b5a42a75eecada48e7887a7c940eKeisuke Kuroyanagi * 1083c40a2301a0b5a42a75eecada48e7887a7c940eKeisuke Kuroyanagi * Unless required by applicable law or agreed to in writing, software 1183c40a2301a0b5a42a75eecada48e7887a7c940eKeisuke Kuroyanagi * distributed under the License is distributed on an "AS IS" BASIS, 1283c40a2301a0b5a42a75eecada48e7887a7c940eKeisuke Kuroyanagi * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 1383c40a2301a0b5a42a75eecada48e7887a7c940eKeisuke Kuroyanagi * See the License for the specific language governing permissions and 1483c40a2301a0b5a42a75eecada48e7887a7c940eKeisuke Kuroyanagi * limitations under the License. 1583c40a2301a0b5a42a75eecada48e7887a7c940eKeisuke Kuroyanagi */ 1683c40a2301a0b5a42a75eecada48e7887a7c940eKeisuke Kuroyanagi 1783c40a2301a0b5a42a75eecada48e7887a7c940eKeisuke Kuroyanagipackage com.android.inputmethod.latin; 1883c40a2301a0b5a42a75eecada48e7887a7c940eKeisuke Kuroyanagi 1986f36003fd4397143bd37938dda029e5707634afYohei Yukawaimport android.text.TextUtils; 20e708b1bc2e11285ad404133b8de21719ce08acb5Keisuke Kuroyanagi 21e708b1bc2e11285ad404133b8de21719ce08acb5Keisuke Kuroyanagiimport com.android.inputmethod.latin.utils.StringUtils; 22e708b1bc2e11285ad404133b8de21719ce08acb5Keisuke Kuroyanagi 2386f36003fd4397143bd37938dda029e5707634afYohei Yukawaimport java.util.Arrays; 2486f36003fd4397143bd37938dda029e5707634afYohei Yukawa 25a790c5b68324da41428aeb68594d43ca5632f66dKeisuke Kuroyanagi/** 26a790c5b68324da41428aeb68594d43ca5632f66dKeisuke Kuroyanagi * Class to represent information of previous words. This class is used to add n-gram entries 27a790c5b68324da41428aeb68594d43ca5632f66dKeisuke Kuroyanagi * into binary dictionaries, to get predictions, and to get suggestions. 28a790c5b68324da41428aeb68594d43ca5632f66dKeisuke Kuroyanagi */ 2983c40a2301a0b5a42a75eecada48e7887a7c940eKeisuke Kuroyanagipublic class PrevWordsInfo { 30e708b1bc2e11285ad404133b8de21719ce08acb5Keisuke Kuroyanagi public static final PrevWordsInfo EMPTY_PREV_WORDS_INFO = 31e708b1bc2e11285ad404133b8de21719ce08acb5Keisuke Kuroyanagi new PrevWordsInfo(WordInfo.EMPTY_WORD_INFO); 321c2f1ada8305e36defa8572da687a4596bf083eaKeisuke Kuroyanagi public static final PrevWordsInfo BEGINNING_OF_SENTENCE = 331c2f1ada8305e36defa8572da687a4596bf083eaKeisuke Kuroyanagi new PrevWordsInfo(WordInfo.BEGINNING_OF_SENTENCE); 341adca93381d261a6070be2721dbf8b8abafbfe01Keisuke Kuroyanagi 35e708b1bc2e11285ad404133b8de21719ce08acb5Keisuke Kuroyanagi /** 36e708b1bc2e11285ad404133b8de21719ce08acb5Keisuke Kuroyanagi * Word information used to represent previous words information. 37e708b1bc2e11285ad404133b8de21719ce08acb5Keisuke Kuroyanagi */ 38e708b1bc2e11285ad404133b8de21719ce08acb5Keisuke Kuroyanagi public static class WordInfo { 39e708b1bc2e11285ad404133b8de21719ce08acb5Keisuke Kuroyanagi public static final WordInfo EMPTY_WORD_INFO = new WordInfo(null); 40e708b1bc2e11285ad404133b8de21719ce08acb5Keisuke Kuroyanagi public static final WordInfo BEGINNING_OF_SENTENCE = new WordInfo(); 41e708b1bc2e11285ad404133b8de21719ce08acb5Keisuke Kuroyanagi 4286f36003fd4397143bd37938dda029e5707634afYohei Yukawa // This is an empty char sequence when mIsBeginningOfSentence is true. 4386f36003fd4397143bd37938dda029e5707634afYohei Yukawa public final CharSequence mWord; 44e708b1bc2e11285ad404133b8de21719ce08acb5Keisuke Kuroyanagi // TODO: Have sentence separator. 45e708b1bc2e11285ad404133b8de21719ce08acb5Keisuke Kuroyanagi // Whether the current context is beginning of sentence or not. This is true when composing 46e708b1bc2e11285ad404133b8de21719ce08acb5Keisuke Kuroyanagi // at the beginning of an input field or composing a word after a sentence separator. 47e708b1bc2e11285ad404133b8de21719ce08acb5Keisuke Kuroyanagi public final boolean mIsBeginningOfSentence; 48e708b1bc2e11285ad404133b8de21719ce08acb5Keisuke Kuroyanagi 49e708b1bc2e11285ad404133b8de21719ce08acb5Keisuke Kuroyanagi // Beginning of sentence. 50e708b1bc2e11285ad404133b8de21719ce08acb5Keisuke Kuroyanagi public WordInfo() { 51e708b1bc2e11285ad404133b8de21719ce08acb5Keisuke Kuroyanagi mWord = ""; 52e708b1bc2e11285ad404133b8de21719ce08acb5Keisuke Kuroyanagi mIsBeginningOfSentence = true; 53e708b1bc2e11285ad404133b8de21719ce08acb5Keisuke Kuroyanagi } 54e708b1bc2e11285ad404133b8de21719ce08acb5Keisuke Kuroyanagi 5586f36003fd4397143bd37938dda029e5707634afYohei Yukawa public WordInfo(final CharSequence word) { 56e708b1bc2e11285ad404133b8de21719ce08acb5Keisuke Kuroyanagi mWord = word; 57e708b1bc2e11285ad404133b8de21719ce08acb5Keisuke Kuroyanagi mIsBeginningOfSentence = false; 58e708b1bc2e11285ad404133b8de21719ce08acb5Keisuke Kuroyanagi } 59e708b1bc2e11285ad404133b8de21719ce08acb5Keisuke Kuroyanagi 60e708b1bc2e11285ad404133b8de21719ce08acb5Keisuke Kuroyanagi public boolean isValid() { 61e708b1bc2e11285ad404133b8de21719ce08acb5Keisuke Kuroyanagi return mWord != null; 62e708b1bc2e11285ad404133b8de21719ce08acb5Keisuke Kuroyanagi } 631c2f1ada8305e36defa8572da687a4596bf083eaKeisuke Kuroyanagi 641c2f1ada8305e36defa8572da687a4596bf083eaKeisuke Kuroyanagi @Override 651c2f1ada8305e36defa8572da687a4596bf083eaKeisuke Kuroyanagi public int hashCode() { 661c2f1ada8305e36defa8572da687a4596bf083eaKeisuke Kuroyanagi return Arrays.hashCode(new Object[] { mWord, mIsBeginningOfSentence } ); 671c2f1ada8305e36defa8572da687a4596bf083eaKeisuke Kuroyanagi } 681c2f1ada8305e36defa8572da687a4596bf083eaKeisuke Kuroyanagi 691c2f1ada8305e36defa8572da687a4596bf083eaKeisuke Kuroyanagi @Override 701c2f1ada8305e36defa8572da687a4596bf083eaKeisuke Kuroyanagi public boolean equals(Object o) { 711c2f1ada8305e36defa8572da687a4596bf083eaKeisuke Kuroyanagi if (this == o) return true; 721c2f1ada8305e36defa8572da687a4596bf083eaKeisuke Kuroyanagi if (!(o instanceof WordInfo)) return false; 731c2f1ada8305e36defa8572da687a4596bf083eaKeisuke Kuroyanagi final WordInfo wordInfo = (WordInfo)o; 741c2f1ada8305e36defa8572da687a4596bf083eaKeisuke Kuroyanagi if (mWord == null || wordInfo.mWord == null) { 751c2f1ada8305e36defa8572da687a4596bf083eaKeisuke Kuroyanagi return mWord == wordInfo.mWord 761c2f1ada8305e36defa8572da687a4596bf083eaKeisuke Kuroyanagi && mIsBeginningOfSentence == wordInfo.mIsBeginningOfSentence; 771c2f1ada8305e36defa8572da687a4596bf083eaKeisuke Kuroyanagi } 7886f36003fd4397143bd37938dda029e5707634afYohei Yukawa return TextUtils.equals(mWord, wordInfo.mWord) 791c2f1ada8305e36defa8572da687a4596bf083eaKeisuke Kuroyanagi && mIsBeginningOfSentence == wordInfo.mIsBeginningOfSentence; 801c2f1ada8305e36defa8572da687a4596bf083eaKeisuke Kuroyanagi } 81e708b1bc2e11285ad404133b8de21719ce08acb5Keisuke Kuroyanagi } 8283c40a2301a0b5a42a75eecada48e7887a7c940eKeisuke Kuroyanagi 83e708b1bc2e11285ad404133b8de21719ce08acb5Keisuke Kuroyanagi // The words immediately before the considered word. EMPTY_WORD_INFO element means we don't 84e708b1bc2e11285ad404133b8de21719ce08acb5Keisuke Kuroyanagi // have any context for that previous word including the "beginning of sentence context" - we 85e708b1bc2e11285ad404133b8de21719ce08acb5Keisuke Kuroyanagi // just don't know what to predict using the information. An example of that is after a comma. 86e708b1bc2e11285ad404133b8de21719ce08acb5Keisuke Kuroyanagi // For simplicity of implementation, elements may also be EMPTY_WORD_INFO transiently after the 87e708b1bc2e11285ad404133b8de21719ce08acb5Keisuke Kuroyanagi // WordComposer was reset and before starting a new composing word, but we should never be 88e708b1bc2e11285ad404133b8de21719ce08acb5Keisuke Kuroyanagi // calling getSuggetions* in this situation. 89e708b1bc2e11285ad404133b8de21719ce08acb5Keisuke Kuroyanagi public WordInfo[] mPrevWordsInfo = new WordInfo[Constants.MAX_PREV_WORD_COUNT_FOR_N_GRAM]; 9017f326b7458c2bde2569e283a96e703755485328Keisuke Kuroyanagi 91e708b1bc2e11285ad404133b8de21719ce08acb5Keisuke Kuroyanagi // Construct from the previous word information. 92e708b1bc2e11285ad404133b8de21719ce08acb5Keisuke Kuroyanagi public PrevWordsInfo(final WordInfo prevWordInfo) { 93e708b1bc2e11285ad404133b8de21719ce08acb5Keisuke Kuroyanagi mPrevWordsInfo[0] = prevWordInfo; 94e708b1bc2e11285ad404133b8de21719ce08acb5Keisuke Kuroyanagi } 95e708b1bc2e11285ad404133b8de21719ce08acb5Keisuke Kuroyanagi 96e708b1bc2e11285ad404133b8de21719ce08acb5Keisuke Kuroyanagi // Construct from WordInfo array. n-th element represents (n+1)-th previous word's information. 97e708b1bc2e11285ad404133b8de21719ce08acb5Keisuke Kuroyanagi public PrevWordsInfo(final WordInfo[] prevWordsInfo) { 98e708b1bc2e11285ad404133b8de21719ce08acb5Keisuke Kuroyanagi for (int i = 0; i < Constants.MAX_PREV_WORD_COUNT_FOR_N_GRAM; i++) { 99e708b1bc2e11285ad404133b8de21719ce08acb5Keisuke Kuroyanagi mPrevWordsInfo[i] = 100e708b1bc2e11285ad404133b8de21719ce08acb5Keisuke Kuroyanagi (prevWordsInfo.length > i) ? prevWordsInfo[i] : WordInfo.EMPTY_WORD_INFO; 101e708b1bc2e11285ad404133b8de21719ce08acb5Keisuke Kuroyanagi } 102e708b1bc2e11285ad404133b8de21719ce08acb5Keisuke Kuroyanagi } 103e708b1bc2e11285ad404133b8de21719ce08acb5Keisuke Kuroyanagi 104e708b1bc2e11285ad404133b8de21719ce08acb5Keisuke Kuroyanagi // Create next prevWordsInfo using current prevWordsInfo. 105e708b1bc2e11285ad404133b8de21719ce08acb5Keisuke Kuroyanagi public PrevWordsInfo getNextPrevWordsInfo(final WordInfo wordInfo) { 106e708b1bc2e11285ad404133b8de21719ce08acb5Keisuke Kuroyanagi final WordInfo[] prevWordsInfo = new WordInfo[Constants.MAX_PREV_WORD_COUNT_FOR_N_GRAM]; 107e708b1bc2e11285ad404133b8de21719ce08acb5Keisuke Kuroyanagi prevWordsInfo[0] = wordInfo; 108e708b1bc2e11285ad404133b8de21719ce08acb5Keisuke Kuroyanagi for (int i = 1; i < prevWordsInfo.length; i++) { 109e708b1bc2e11285ad404133b8de21719ce08acb5Keisuke Kuroyanagi prevWordsInfo[i] = mPrevWordsInfo[i - 1]; 110e708b1bc2e11285ad404133b8de21719ce08acb5Keisuke Kuroyanagi } 111e708b1bc2e11285ad404133b8de21719ce08acb5Keisuke Kuroyanagi return new PrevWordsInfo(prevWordsInfo); 11283c40a2301a0b5a42a75eecada48e7887a7c940eKeisuke Kuroyanagi } 1131adca93381d261a6070be2721dbf8b8abafbfe01Keisuke Kuroyanagi 1141adca93381d261a6070be2721dbf8b8abafbfe01Keisuke Kuroyanagi public boolean isValid() { 115e708b1bc2e11285ad404133b8de21719ce08acb5Keisuke Kuroyanagi return mPrevWordsInfo[0].isValid(); 116e708b1bc2e11285ad404133b8de21719ce08acb5Keisuke Kuroyanagi } 117e708b1bc2e11285ad404133b8de21719ce08acb5Keisuke Kuroyanagi 118e708b1bc2e11285ad404133b8de21719ce08acb5Keisuke Kuroyanagi public void outputToArray(final int[][] codePointArrays, 119e708b1bc2e11285ad404133b8de21719ce08acb5Keisuke Kuroyanagi final boolean[] isBeginningOfSentenceArray) { 120e708b1bc2e11285ad404133b8de21719ce08acb5Keisuke Kuroyanagi for (int i = 0; i < mPrevWordsInfo.length; i++) { 121e708b1bc2e11285ad404133b8de21719ce08acb5Keisuke Kuroyanagi final WordInfo wordInfo = mPrevWordsInfo[i]; 122e708b1bc2e11285ad404133b8de21719ce08acb5Keisuke Kuroyanagi if (wordInfo == null || !wordInfo.isValid()) { 123e708b1bc2e11285ad404133b8de21719ce08acb5Keisuke Kuroyanagi codePointArrays[i] = new int[0]; 124e708b1bc2e11285ad404133b8de21719ce08acb5Keisuke Kuroyanagi isBeginningOfSentenceArray[i] = false; 125e708b1bc2e11285ad404133b8de21719ce08acb5Keisuke Kuroyanagi continue; 126e708b1bc2e11285ad404133b8de21719ce08acb5Keisuke Kuroyanagi } 127e708b1bc2e11285ad404133b8de21719ce08acb5Keisuke Kuroyanagi codePointArrays[i] = StringUtils.toCodePointArray(wordInfo.mWord); 128e708b1bc2e11285ad404133b8de21719ce08acb5Keisuke Kuroyanagi isBeginningOfSentenceArray[i] = wordInfo.mIsBeginningOfSentence; 129e708b1bc2e11285ad404133b8de21719ce08acb5Keisuke Kuroyanagi } 1301adca93381d261a6070be2721dbf8b8abafbfe01Keisuke Kuroyanagi } 131dfca51726e9dc9a35f462dee39331823eafa07c9Keisuke Kuroyanagi 132dfca51726e9dc9a35f462dee39331823eafa07c9Keisuke Kuroyanagi @Override 1331c2f1ada8305e36defa8572da687a4596bf083eaKeisuke Kuroyanagi public int hashCode() { 1341c2f1ada8305e36defa8572da687a4596bf083eaKeisuke Kuroyanagi return Arrays.hashCode(mPrevWordsInfo); 1351c2f1ada8305e36defa8572da687a4596bf083eaKeisuke Kuroyanagi } 1361c2f1ada8305e36defa8572da687a4596bf083eaKeisuke Kuroyanagi 1371c2f1ada8305e36defa8572da687a4596bf083eaKeisuke Kuroyanagi @Override 1381c2f1ada8305e36defa8572da687a4596bf083eaKeisuke Kuroyanagi public boolean equals(Object o) { 1391c2f1ada8305e36defa8572da687a4596bf083eaKeisuke Kuroyanagi if (this == o) return true; 1401c2f1ada8305e36defa8572da687a4596bf083eaKeisuke Kuroyanagi if (!(o instanceof PrevWordsInfo)) return false; 1411c2f1ada8305e36defa8572da687a4596bf083eaKeisuke Kuroyanagi final PrevWordsInfo prevWordsInfo = (PrevWordsInfo)o; 1421c2f1ada8305e36defa8572da687a4596bf083eaKeisuke Kuroyanagi return Arrays.equals(mPrevWordsInfo, prevWordsInfo.mPrevWordsInfo); 1431c2f1ada8305e36defa8572da687a4596bf083eaKeisuke Kuroyanagi } 1441c2f1ada8305e36defa8572da687a4596bf083eaKeisuke Kuroyanagi 1451c2f1ada8305e36defa8572da687a4596bf083eaKeisuke Kuroyanagi @Override 146dfca51726e9dc9a35f462dee39331823eafa07c9Keisuke Kuroyanagi public String toString() { 147e708b1bc2e11285ad404133b8de21719ce08acb5Keisuke Kuroyanagi final StringBuffer builder = new StringBuffer(); 148e708b1bc2e11285ad404133b8de21719ce08acb5Keisuke Kuroyanagi for (int i = 0; i < mPrevWordsInfo.length; i++) { 149e708b1bc2e11285ad404133b8de21719ce08acb5Keisuke Kuroyanagi final WordInfo wordInfo = mPrevWordsInfo[i]; 150e708b1bc2e11285ad404133b8de21719ce08acb5Keisuke Kuroyanagi builder.append("PrevWord["); 151e708b1bc2e11285ad404133b8de21719ce08acb5Keisuke Kuroyanagi builder.append(i); 152e708b1bc2e11285ad404133b8de21719ce08acb5Keisuke Kuroyanagi builder.append("]: "); 1531c2f1ada8305e36defa8572da687a4596bf083eaKeisuke Kuroyanagi if (wordInfo == null || !wordInfo.isValid()) { 154e708b1bc2e11285ad404133b8de21719ce08acb5Keisuke Kuroyanagi builder.append("Empty. "); 155e708b1bc2e11285ad404133b8de21719ce08acb5Keisuke Kuroyanagi continue; 156e708b1bc2e11285ad404133b8de21719ce08acb5Keisuke Kuroyanagi } 157e708b1bc2e11285ad404133b8de21719ce08acb5Keisuke Kuroyanagi builder.append(wordInfo.mWord); 158e708b1bc2e11285ad404133b8de21719ce08acb5Keisuke Kuroyanagi builder.append(", isBeginningOfSentence: "); 159e708b1bc2e11285ad404133b8de21719ce08acb5Keisuke Kuroyanagi builder.append(wordInfo.mIsBeginningOfSentence); 160e708b1bc2e11285ad404133b8de21719ce08acb5Keisuke Kuroyanagi builder.append(". "); 161e708b1bc2e11285ad404133b8de21719ce08acb5Keisuke Kuroyanagi } 162e708b1bc2e11285ad404133b8de21719ce08acb5Keisuke Kuroyanagi return builder.toString(); 163dfca51726e9dc9a35f462dee39331823eafa07c9Keisuke Kuroyanagi } 16483c40a2301a0b5a42a75eecada48e7887a7c940eKeisuke Kuroyanagi} 165