1/*
2 * Copyright (C) 2014 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 */
16package com.android.tv.util;
17
18import android.os.SystemClock;
19
20/**
21 * An interface through which system clocks can be read. The {@link #SYSTEM} implementation
22 * must be used for all non-test cases.
23 */
24public interface Clock {
25    /**
26     * Returns the current time in milliseconds since January 1, 1970 00:00:00.0 UTC.
27     * See {@link System#currentTimeMillis()}.
28     */
29    long currentTimeMillis();
30
31    /**
32     * Returns milliseconds since boot, including time spent in sleep.
33     *
34     * @see SystemClock#elapsedRealtime()
35     */
36    long elapsedRealtime();
37
38    /**
39     * Waits a given number of milliseconds (of uptimeMillis) before returning.
40     *
41     * @param ms to sleep before returning, in milliseconds of uptime.
42     * @see SystemClock#sleep(long)
43     */
44    void sleep(long ms);
45
46    /**
47     * The default implementation of Clock.
48     */
49    Clock SYSTEM = new Clock() {
50        @Override
51        public long currentTimeMillis() {
52            return System.currentTimeMillis();
53        }
54
55        @Override
56        public long elapsedRealtime() {
57            return SystemClock.elapsedRealtime();
58        }
59
60        @Override
61        public void sleep(long ms) {
62            SystemClock.sleep(ms);
63        }
64    };
65}
66