1/*
2 * Copyright (C) 2011 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.support.v4.util;
18
19import android.support.annotation.RestrictTo;
20import android.util.Log;
21
22import java.io.Writer;
23
24import static android.support.annotation.RestrictTo.Scope.GROUP_ID;
25
26/**
27 * Helper for accessing features in {@link android.util.LogWriter}
28 * introduced after API level 4 in a backwards compatible fashion.
29 *
30 * @hide
31 */
32@RestrictTo(GROUP_ID)
33public class LogWriter extends Writer {
34    private final String mTag;
35    private StringBuilder mBuilder = new StringBuilder(128);
36
37    /**
38     * Create a new Writer that sends to the log with the given priority
39     * and tag.
40     *
41     * @param tag A string tag to associate with each printed log statement.
42     */
43    public LogWriter(String tag) {
44        mTag = tag;
45    }
46
47    @Override public void close() {
48        flushBuilder();
49    }
50
51    @Override public void flush() {
52        flushBuilder();
53    }
54
55    @Override public void write(char[] buf, int offset, int count) {
56        for(int i = 0; i < count; i++) {
57            char c = buf[offset + i];
58            if ( c == '\n') {
59                flushBuilder();
60            }
61            else {
62                mBuilder.append(c);
63            }
64        }
65    }
66
67    private void flushBuilder() {
68        if (mBuilder.length() > 0) {
69            Log.d(mTag, mBuilder.toString());
70            mBuilder.delete(0, mBuilder.length());
71        }
72    }
73}
74