Hyphenator.java revision 71cbc72e70a6f0e086535c51e35262eb3a4d4bd9 
1/*
2 * Copyright (C) 2015 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 android.text;
18
19import android.util.Log;
20
21import java.io.File;
22import java.io.IOException;
23import java.io.RandomAccessFile;
24import java.util.HashMap;
25import java.util.Locale;
26
27/**
28 * Hyphenator is a wrapper class for a native implementation of automatic hyphenation,
29 * in essence finding valid hyphenation opportunities in a word.
30 *
31 * @hide
32 */
33/* package */ class Hyphenator {
34    // This class has deliberately simple lifetime management (no finalizer) because in
35    // the common case a process will use a very small number of locales.
36
37    private static String TAG = "Hyphenator";
38
39    static HashMap<Locale, Hyphenator> sMap = new HashMap<Locale, Hyphenator>();
40
41    private long mNativePtr;
42
43    private Hyphenator(long nativePtr) {
44        mNativePtr = nativePtr;
45    }
46
47    public static long get(Locale locale) {
48        synchronized (sMap) {
49            Hyphenator result = sMap.get(locale);
50            if (result == null) {
51                result = loadHyphenator(locale);
52                sMap.put(locale, result);
53            }
54            return result == null ? 0 : result.mNativePtr;
55        }
56    }
57
58    private static Hyphenator loadHyphenator(Locale locale) {
59        // TODO: find pattern dictionary (from system location) that best matches locale
60        if (Locale.US.equals(locale)) {
61            File f = new File("/data/local/tmp/hyph-en-us.pat.txt");
62            try {
63                RandomAccessFile rf = new RandomAccessFile(f, "r");
64                byte[] buf = new byte[(int)rf.length()];
65                rf.read(buf);
66                rf.close();
67                String patternData = new String(buf);
68                long nativePtr = StaticLayout.nLoadHyphenator(patternData);
69                return new Hyphenator(nativePtr);
70            } catch (IOException e) {
71                Log.e(TAG, "error loading hyphenation " + f);
72            }
73        }
74        return null;
75    }
76}
77