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 17 package com.android.tv.analytics; 18 19 import android.os.SystemClock; 20 21 /** 22 * Times a duration. 23 */ 24 public final class DurationTimer { 25 public static final long TIME_NOT_SET = -1; 26 27 private long startTimeMs = TIME_NOT_SET; 28 29 /** 30 * Returns true if the timer is running. 31 */ 32 public boolean isRunning() { 33 return startTimeMs != TIME_NOT_SET; 34 } 35 36 /** 37 * Start the timer. 38 */ 39 public void start() { 40 startTimeMs = SystemClock.elapsedRealtime(); 41 } 42 43 /** 44 * Returns the current duration in milliseconds or {@link #TIME_NOT_SET} if the timer is not 45 * running. 46 */ 47 public long getDuration() { 48 return isRunning() ? SystemClock.elapsedRealtime() - startTimeMs : TIME_NOT_SET; 49 } 50 51 /** 52 * Stops the timer and resets its value to {@link #TIME_NOT_SET}. 53 * 54 * @return the current duration in milliseconds or {@link #TIME_NOT_SET} if the timer is not 55 * running. 56 */ 57 public long reset() { 58 long duration = getDuration(); 59 startTimeMs = TIME_NOT_SET; 60 return duration; 61 } 62 } 63
