001/* 002 * Copyright (C) 2008 The Guava Authors 003 * 004 * Licensed under the Apache License, Version 2.0 (the "License"); 005 * you may not use this file except in compliance with the License. 006 * You may obtain a copy of the License at 007 * 008 * http://www.apache.org/licenses/LICENSE-2.0 009 * 010 * Unless required by applicable law or agreed to in writing, software 011 * distributed under the License is distributed on an "AS IS" BASIS, 012 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 013 * See the License for the specific language governing permissions and 014 * limitations under the License. 015 */ 016 017package com.google.common.testing; 018 019import static com.google.common.base.Preconditions.checkArgument; 020 021import com.google.common.annotations.GwtCompatible; 022import com.google.common.annotations.GwtIncompatible; 023import com.google.common.annotations.J2ktIncompatible; 024import com.google.common.base.Ticker; 025import com.google.errorprone.annotations.CanIgnoreReturnValue; 026import java.time.Duration; 027import java.util.concurrent.TimeUnit; 028import java.util.concurrent.atomic.AtomicLong; 029 030/** 031 * A Ticker whose value can be advanced programmatically in test. 032 * 033 * <p>The ticker can be configured so that the time is incremented whenever {@link #read} is called: 034 * see {@link #setAutoIncrementStep}. 035 * 036 * <p>This class is thread-safe. 037 * 038 * @author Jige Yu 039 * @since 10.0 040 */ 041@ElementTypesAreNonnullByDefault 042@GwtCompatible 043public class FakeTicker extends Ticker { 044 045 private final AtomicLong nanos = new AtomicLong(); 046 private volatile long autoIncrementStepNanos; 047 048 /** Advances the ticker value by {@code time} in {@code timeUnit}. */ 049 @SuppressWarnings("GoodTime") // should accept a java.time.Duration 050 @CanIgnoreReturnValue 051 public FakeTicker advance(long time, TimeUnit timeUnit) { 052 return advance(timeUnit.toNanos(time)); 053 } 054 055 /** Advances the ticker value by {@code nanoseconds}. */ 056 @SuppressWarnings("GoodTime") // should accept a java.time.Duration 057 @CanIgnoreReturnValue 058 public FakeTicker advance(long nanoseconds) { 059 nanos.addAndGet(nanoseconds); 060 return this; 061 } 062 063 /** 064 * Advances the ticker value by {@code duration}. 065 * 066 * @since 28.0 067 */ 068 @GwtIncompatible 069 @J2ktIncompatible 070 @CanIgnoreReturnValue 071 @SuppressWarnings("Java7ApiChecker") // guava-android can rely on library desugaring now. 072 public FakeTicker advance(Duration duration) { 073 return advance(duration.toNanos()); 074 } 075 076 /** 077 * Sets the increment applied to the ticker whenever it is queried. 078 * 079 * <p>The default behavior is to auto increment by zero. i.e: The ticker is left unchanged when 080 * queried. 081 */ 082 @SuppressWarnings("GoodTime") // should accept a java.time.Duration 083 @CanIgnoreReturnValue 084 public FakeTicker setAutoIncrementStep(long autoIncrementStep, TimeUnit timeUnit) { 085 checkArgument(autoIncrementStep >= 0, "May not auto-increment by a negative amount"); 086 this.autoIncrementStepNanos = timeUnit.toNanos(autoIncrementStep); 087 return this; 088 } 089 090 /** 091 * Sets the increment applied to the ticker whenever it is queried. 092 * 093 * <p>The default behavior is to auto increment by zero. i.e: The ticker is left unchanged when 094 * queried. 095 * 096 * @since 28.0 097 */ 098 @GwtIncompatible 099 @J2ktIncompatible 100 @CanIgnoreReturnValue 101 @SuppressWarnings("Java7ApiChecker") // guava-android can rely on library desugaring now. 102 public FakeTicker setAutoIncrementStep(Duration autoIncrementStep) { 103 return setAutoIncrementStep(autoIncrementStep.toNanos(), TimeUnit.NANOSECONDS); 104 } 105 106 @Override 107 public long read() { 108 return nanos.getAndAdd(autoIncrementStepNanos); 109 } 110}