1 /*
2  * Copyright (C) 2013 The Android Open Source Project
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *      http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 
17 package com.android.inputmethod.latin.makedict;
18 
19 import com.android.inputmethod.annotations.UsedForTesting;
20 import com.android.inputmethod.latin.BinaryDictionary;
21 import com.android.inputmethod.latin.utils.FileUtils;
22 
23 import java.io.File;
24 import java.io.FileNotFoundException;
25 import java.io.IOException;
26 import java.util.ArrayList;
27 
28 /**
29  * An implementation of binary dictionary decoder for version 4 binary dictionary.
30  */
31 @UsedForTesting
32 public class Ver4DictDecoder extends AbstractDictDecoder {
33     final File mDictDirectory;
34 
35     @UsedForTesting
Ver4DictDecoder(final File dictDirectory, final int factoryFlag)36     /* package */ Ver4DictDecoder(final File dictDirectory, final int factoryFlag) {
37         this(dictDirectory, null /* factory */);
38     }
39 
40     @UsedForTesting
Ver4DictDecoder(final File dictDirectory, final DictionaryBufferFactory factory)41     /* package */ Ver4DictDecoder(final File dictDirectory, final DictionaryBufferFactory factory) {
42         mDictDirectory = dictDirectory;
43 
44     }
45 
46     @Override
readHeader()47     public DictionaryHeader readHeader() throws IOException, UnsupportedFormatException {
48         // dictType is not being used in dicttool. Passing an empty string.
49         final BinaryDictionary binaryDictionary= new BinaryDictionary(
50               mDictDirectory.getAbsolutePath(), 0 /* offset */, 0 /* length */,
51               true /* useFullEditDistance */, null /* locale */,
52               "" /* dictType */, true /* isUpdatable */);
53         final DictionaryHeader header = binaryDictionary.getHeader();
54         binaryDictionary.close();
55         if (header == null) {
56             throw new IOException("Cannot read the dictionary header.");
57         }
58         return header;
59     }
60 
61     @Override
readDictionaryBinary(final boolean deleteDictIfBroken)62     public FusionDictionary readDictionaryBinary(final boolean deleteDictIfBroken)
63             throws FileNotFoundException, IOException, UnsupportedFormatException {
64         // dictType is not being used in dicttool. Passing an empty string.
65         final BinaryDictionary binaryDictionary = new BinaryDictionary(
66               mDictDirectory.getAbsolutePath(), 0 /* offset */, 0 /* length */,
67               true /* useFullEditDistance */, null /* locale */,
68               "" /* dictType */, true /* isUpdatable */);
69         final DictionaryHeader header = readHeader();
70         final FusionDictionary fusionDict =
71                 new FusionDictionary(new FusionDictionary.PtNodeArray(), header.mDictionaryOptions);
72         int token = 0;
73         final ArrayList<WordProperty> wordProperties = new ArrayList<>();
74         do {
75             final BinaryDictionary.GetNextWordPropertyResult result =
76                     binaryDictionary.getNextWordProperty(token);
77             final WordProperty wordProperty = result.mWordProperty;
78             if (wordProperty == null) {
79                 binaryDictionary.close();
80                 if (deleteDictIfBroken) {
81                     FileUtils.deleteRecursively(mDictDirectory);
82                 }
83                 return null;
84             }
85             wordProperties.add(wordProperty);
86             token = result.mNextToken;
87         } while (token != 0);
88 
89         // Insert unigrams into the fusion dictionary.
90         for (final WordProperty wordProperty : wordProperties) {
91             if (wordProperty.mIsBlacklistEntry) {
92                 fusionDict.addBlacklistEntry(wordProperty.mWord, wordProperty.mShortcutTargets,
93                         wordProperty.mIsNotAWord);
94             } else {
95                 fusionDict.add(wordProperty.mWord, wordProperty.mProbabilityInfo,
96                         wordProperty.mShortcutTargets, wordProperty.mIsNotAWord);
97             }
98         }
99         // Insert bigrams into the fusion dictionary.
100         for (final WordProperty wordProperty : wordProperties) {
101             if (wordProperty.mBigrams == null) {
102                 continue;
103             }
104             final String word0 = wordProperty.mWord;
105             for (final WeightedString bigram : wordProperty.mBigrams) {
106                 fusionDict.setBigram(word0, bigram.mWord, bigram.mProbabilityInfo);
107             }
108         }
109         binaryDictionary.close();
110         return fusionDict;
111     }
112 }
113