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
17package com.android.inputmethod.latin.makedict;
18
19import com.android.inputmethod.annotations.UsedForTesting;
20
21import java.io.FileNotFoundException;
22import java.io.IOException;
23import java.util.ArrayList;
24import java.util.TreeMap;
25
26/**
27 * A base class of the binary dictionary decoder.
28 */
29public abstract class AbstractDictDecoder implements DictDecoder {
30    private static final int SUCCESS = 0;
31    private static final int ERROR_CANNOT_READ = 1;
32    private static final int ERROR_WRONG_FORMAT = 2;
33
34    @Override @UsedForTesting
35    public int getTerminalPosition(final String word)
36            throws IOException, UnsupportedFormatException {
37        if (!isDictBufferOpen()) {
38            openDictBuffer();
39        }
40        return BinaryDictIOUtils.getTerminalPosition(this, word);
41    }
42
43    @Override @UsedForTesting
44    public void readUnigramsAndBigramsBinary(final TreeMap<Integer, String> words,
45            final TreeMap<Integer, Integer> frequencies,
46            final TreeMap<Integer, ArrayList<PendingAttribute>> bigrams)
47            throws IOException, UnsupportedFormatException {
48        if (!isDictBufferOpen()) {
49            openDictBuffer();
50        }
51        BinaryDictIOUtils.readUnigramsAndBigramsBinary(this, words, frequencies, bigrams);
52    }
53
54    /**
55     * Check whether the header contains the expected information. This is a no-error method,
56     * that will return an error code and never throw a checked exception.
57     * @return an error code, either ERROR_* or SUCCESS.
58     */
59    private int checkHeader() {
60        try {
61            readHeader();
62        } catch (IOException e) {
63            return ERROR_CANNOT_READ;
64        } catch (UnsupportedFormatException e) {
65            return ERROR_WRONG_FORMAT;
66        }
67        return SUCCESS;
68    }
69
70    @Override
71    public boolean hasValidRawBinaryDictionary() {
72        return checkHeader() == SUCCESS;
73    }
74
75    // Placeholder implementations below. These are actually unused.
76    @Override
77    public void openDictBuffer() throws FileNotFoundException, IOException,
78            UnsupportedFormatException {
79    }
80
81    @Override
82    public boolean isDictBufferOpen() {
83        return false;
84    }
85
86    @Override
87    public PtNodeInfo readPtNode(final int ptNodePos) {
88        return null;
89    }
90
91    @Override
92    public void setPosition(int newPos) {
93    }
94
95    @Override
96    public int getPosition() {
97        return 0;
98    }
99
100    @Override
101    public int readPtNodeCount() {
102        return 0;
103    }
104}
105