001/*
002 * Copyright (C) 2011 The Guava Authors
003 *
004 * Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except
005 * in compliance with the License. You may obtain a copy of the License at
006 *
007 * http://www.apache.org/licenses/LICENSE-2.0
008 *
009 * Unless required by applicable law or agreed to in writing, software distributed under the License
010 * is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express
011 * or implied. See the License for the specific language governing permissions and limitations under
012 * the License.
013 */
014
015package com.google.common.util.concurrent;
016
017import com.google.common.annotations.GwtIncompatible;
018import com.google.common.collect.ForwardingObject;
019import com.google.errorprone.annotations.CanIgnoreReturnValue;
020import java.util.Collection;
021import java.util.List;
022import java.util.concurrent.Callable;
023import java.util.concurrent.ExecutionException;
024import java.util.concurrent.ExecutorService;
025import java.util.concurrent.Future;
026import java.util.concurrent.TimeUnit;
027import java.util.concurrent.TimeoutException;
028
029/**
030 * An executor service which forwards all its method calls to another executor service. Subclasses
031 * should override one or more methods to modify the behavior of the backing executor service as
032 * desired per the <a href="http://en.wikipedia.org/wiki/Decorator_pattern">decorator pattern</a>.
033 *
034 * @author Kurt Alfred Kluever
035 * @since 10.0
036 */
037@CanIgnoreReturnValue // TODO(cpovirk): Consider being more strict.
038@GwtIncompatible
039public abstract class ForwardingExecutorService extends ForwardingObject
040    implements ExecutorService {
041  /** Constructor for use by subclasses. */
042  protected ForwardingExecutorService() {}
043
044  @Override
045  protected abstract ExecutorService delegate();
046
047  @Override
048  public boolean awaitTermination(long timeout, TimeUnit unit) throws InterruptedException {
049    return delegate().awaitTermination(timeout, unit);
050  }
051
052  @Override
053  public <T> List<Future<T>> invokeAll(Collection<? extends Callable<T>> tasks)
054      throws InterruptedException {
055    return delegate().invokeAll(tasks);
056  }
057
058  @Override
059  public <T> List<Future<T>> invokeAll(
060      Collection<? extends Callable<T>> tasks, long timeout, TimeUnit unit)
061      throws InterruptedException {
062    return delegate().invokeAll(tasks, timeout, unit);
063  }
064
065  @Override
066  public <T> T invokeAny(Collection<? extends Callable<T>> tasks)
067      throws InterruptedException, ExecutionException {
068    return delegate().invokeAny(tasks);
069  }
070
071  @Override
072  public <T> T invokeAny(Collection<? extends Callable<T>> tasks, long timeout, TimeUnit unit)
073      throws InterruptedException, ExecutionException, TimeoutException {
074    return delegate().invokeAny(tasks, timeout, unit);
075  }
076
077  @Override
078  public boolean isShutdown() {
079    return delegate().isShutdown();
080  }
081
082  @Override
083  public boolean isTerminated() {
084    return delegate().isTerminated();
085  }
086
087  @Override
088  public void shutdown() {
089    delegate().shutdown();
090  }
091
092  @Override
093  public List<Runnable> shutdownNow() {
094    return delegate().shutdownNow();
095  }
096
097  @Override
098  public void execute(Runnable command) {
099    delegate().execute(command);
100  }
101
102  public <T> Future<T> submit(Callable<T> task) {
103    return delegate().submit(task);
104  }
105
106  @Override
107  public Future<?> submit(Runnable task) {
108    return delegate().submit(task);
109  }
110
111  @Override
112  public <T> Future<T> submit(Runnable task, T result) {
113    return delegate().submit(task, result);
114  }
115}