1 /* 2 * Copyright (C) 2009 Google Inc. 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.util.concurrent; 18 19 import com.google.common.collect.ForwardingObject; 20 21 import java.util.concurrent.ExecutionException; 22 import java.util.concurrent.Future; 23 import java.util.concurrent.TimeUnit; 24 import java.util.concurrent.TimeoutException; 25 26 /** 27 * A {@link Future} which forwards all its method calls to another future. 28 * Subclasses should override one or more methods to modify the behavior of 29 * the backing collection as desired per the <a 30 * href="http://en.wikipedia.org/wiki/Decorator_pattern">decorator pattern</a>. 31 * 32 * @see ForwardingObject 33 * @author Sven Mawson 34 * @since 2009.09.15 <b>tentative</b> 35 */ 36 public abstract class ForwardingFuture<V> extends ForwardingObject 37 implements Future<V> { 38 39 @Override protected abstract Future<V> delegate(); 40 41 /*@Override*/ 42 public boolean cancel(boolean mayInterruptIfRunning) { 43 return delegate().cancel(mayInterruptIfRunning); 44 } 45 46 /*@Override*/ 47 public boolean isCancelled() { 48 return delegate().isCancelled(); 49 } 50 51 /*@Override*/ 52 public boolean isDone() { 53 return delegate().isDone(); 54 } 55 56 /*@Override*/ 57 public V get() throws InterruptedException, ExecutionException { 58 return delegate().get(); 59 } 60 61 /*@Override*/ 62 public V get(long timeout, TimeUnit unit) 63 throws InterruptedException, ExecutionException, TimeoutException { 64 return delegate().get(timeout, unit); 65 } 66 } 67
