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