1 /* 2 * Copyright (C) 2008 The Guava Authors 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.google.common.testing; 18 19 import static com.google.common.base.Preconditions.checkArgument; 20 21 import com.google.common.annotations.Beta; 22 import com.google.common.annotations.GwtCompatible; 23 import com.google.common.annotations.GwtIncompatible; 24 import com.google.common.base.Ticker; 25 import java.util.concurrent.TimeUnit; 26 import java.util.concurrent.atomic.AtomicLong; 27 28 /** 29 * A Ticker whose value can be advanced programmatically in test. 30 * 31 * <p>The ticker can be configured so that the time is incremented whenever {@link #read} is called: 32 * see {@link #setAutoIncrementStep}. 33 * 34 * <p>This class is thread-safe. 35 * 36 * @author Jige Yu 37 * @since 10.0 38 */ 39 @Beta 40 @GwtCompatible 41 public class FakeTicker extends Ticker { 42 43 private final AtomicLong nanos = new AtomicLong(); 44 private volatile long autoIncrementStepNanos; 45 46 /** Advances the ticker value by {@code time} in {@code timeUnit}. */ 47 @SuppressWarnings("GoodTime") // should accept a java.time.Duration advance(long time, TimeUnit timeUnit)48 public FakeTicker advance(long time, TimeUnit timeUnit) { 49 return advance(timeUnit.toNanos(time)); 50 } 51 52 /** Advances the ticker value by {@code nanoseconds}. */ 53 @SuppressWarnings("GoodTime") // should accept a java.time.Duration advance(long nanoseconds)54 public FakeTicker advance(long nanoseconds) { 55 nanos.addAndGet(nanoseconds); 56 return this; 57 } 58 59 /** 60 * Advances the ticker value by {@code duration}. 61 * 62 * @since 28.0 63 */ 64 @GwtIncompatible advance(java.time.Duration duration)65 public FakeTicker advance(java.time.Duration duration) { 66 return advance(duration.toNanos()); 67 } 68 69 /** 70 * Sets the increment applied to the ticker whenever it is queried. 71 * 72 * <p>The default behavior is to auto increment by zero. i.e: The ticker is left unchanged when 73 * queried. 74 */ 75 @SuppressWarnings("GoodTime") // should accept a java.time.Duration setAutoIncrementStep(long autoIncrementStep, TimeUnit timeUnit)76 public FakeTicker setAutoIncrementStep(long autoIncrementStep, TimeUnit timeUnit) { 77 checkArgument(autoIncrementStep >= 0, "May not auto-increment by a negative amount"); 78 this.autoIncrementStepNanos = timeUnit.toNanos(autoIncrementStep); 79 return this; 80 } 81 82 /** 83 * Sets the increment applied to the ticker whenever it is queried. 84 * 85 * <p>The default behavior is to auto increment by zero. i.e: The ticker is left unchanged when 86 * queried. 87 * 88 * @since 28.0 89 */ 90 @GwtIncompatible setAutoIncrementStep(java.time.Duration autoIncrementStep)91 public FakeTicker setAutoIncrementStep(java.time.Duration autoIncrementStep) { 92 return setAutoIncrementStep(autoIncrementStep.toNanos(), TimeUnit.NANOSECONDS); 93 } 94 95 @Override read()96 public long read() { 97 return nanos.getAndAdd(autoIncrementStepNanos); 98 } 99 } 100