1/*
2 * Copyright (C) 2010 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.email;
18
19import com.android.emailcommon.Logging;
20import com.android.mail.utils.LogUtils;
21
22import android.os.SystemClock;
23
24/**
25 * A simple class to measure elapsed time.
26 *
27 * <code>
28 *   StopWatch s = StopWatch.start();
29 *   // Do your stuff
30 *   s.split();
31 *   // More stuff
32 *   s.split();
33 *   // More stuff
34 *   s.stop();
35 * </code>
36 */
37public class StopWatch {
38    private final String mName;
39    private final long mStart;
40    private long mLastSplit;
41
42    private StopWatch(String name) {
43        mName = name;
44        mStart = getCurrentTime();
45        mLastSplit = mStart;
46        LogUtils.w(Logging.LOG_TAG, "StopWatch(" + mName + ") start");
47    }
48
49    public static StopWatch start(String name) {
50        return new StopWatch(name);
51    }
52
53    public void split(String label) {
54        long now = getCurrentTime() ;
55        long elapse = now - mLastSplit;
56        LogUtils.w(Logging.LOG_TAG, "StopWatch(" + mName + ") split(" + label + ") " + elapse);
57        mLastSplit = now;
58    }
59
60    public void stop() {
61        long now = getCurrentTime();
62        LogUtils.w(Logging.LOG_TAG, "StopWatch(" + mName + ") stop: "
63                + (now - mLastSplit)
64                + "  (total " + (now - mStart) + ")");
65    }
66
67    private static long getCurrentTime() {
68        // We might want to use other counters, such as currentThreadTimeMillis().
69        // TODO add option for that?
70        return SystemClock.elapsedRealtime();
71    }
72}
73