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; 028import org.checkerframework.checker.nullness.qual.Nullable; 029 030/** 031 * An executor service which forwards all its method calls to another executor service. Subclasses 032 * should override one or more methods to modify the behavior of the backing executor service as 033 * desired per the <a href="http://en.wikipedia.org/wiki/Decorator_pattern">decorator pattern</a>. 034 * 035 * @author Kurt Alfred Kluever 036 * @since 10.0 037 */ 038@CanIgnoreReturnValue // TODO(cpovirk): Consider being more strict. 039@GwtIncompatible 040@ElementTypesAreNonnullByDefault 041public abstract class ForwardingExecutorService extends ForwardingObject 042 implements ExecutorService { 043 /** Constructor for use by subclasses. */ 044 protected ForwardingExecutorService() {} 045 046 @Override 047 protected abstract ExecutorService delegate(); 048 049 @Override 050 public boolean awaitTermination(long timeout, TimeUnit unit) throws InterruptedException { 051 return delegate().awaitTermination(timeout, unit); 052 } 053 054 @Override 055 public <T extends @Nullable Object> List<Future<T>> invokeAll( 056 Collection<? extends Callable<T>> tasks) throws InterruptedException { 057 return delegate().invokeAll(tasks); 058 } 059 060 @Override 061 public <T extends @Nullable Object> List<Future<T>> invokeAll( 062 Collection<? extends Callable<T>> tasks, long timeout, TimeUnit unit) 063 throws InterruptedException { 064 return delegate().invokeAll(tasks, timeout, unit); 065 } 066 067 @Override 068 public <T extends @Nullable Object> T invokeAny(Collection<? extends Callable<T>> tasks) 069 throws InterruptedException, ExecutionException { 070 return delegate().invokeAny(tasks); 071 } 072 073 @Override 074 public <T extends @Nullable Object> T invokeAny( 075 Collection<? extends Callable<T>> tasks, long timeout, TimeUnit unit) 076 throws InterruptedException, ExecutionException, TimeoutException { 077 return delegate().invokeAny(tasks, timeout, unit); 078 } 079 080 @Override 081 public boolean isShutdown() { 082 return delegate().isShutdown(); 083 } 084 085 @Override 086 public boolean isTerminated() { 087 return delegate().isTerminated(); 088 } 089 090 @Override 091 public void shutdown() { 092 delegate().shutdown(); 093 } 094 095 @Override 096 public List<Runnable> shutdownNow() { 097 return delegate().shutdownNow(); 098 } 099 100 @Override 101 public void execute(Runnable command) { 102 delegate().execute(command); 103 } 104 105 @Override 106 public <T extends @Nullable Object> Future<T> submit(Callable<T> task) { 107 return delegate().submit(task); 108 } 109 110 @Override 111 public Future<?> submit(Runnable task) { 112 return delegate().submit(task); 113 } 114 115 @Override 116 public <T extends @Nullable Object> Future<T> submit( 117 Runnable task, @ParametricNullness T result) { 118 return delegate().submit(task, result); 119 } 120}