001 /* 002 * Copyright (C) 2011 The Guava Authors 003 * 004 * Licensed under the Apache License, Version 2.0 (the "License"); 005 * you may not use this file except in compliance with the License. 006 * You may obtain a copy of the License at 007 * 008 * http://www.apache.org/licenses/LICENSE-2.0 009 * 010 * Unless required by applicable law or agreed to in writing, software 011 * distributed under the License is distributed on an "AS IS" BASIS, 012 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 013 * See the License for the specific language governing permissions and 014 * limitations under the License. 015 */ 016 017 package com.google.common.util.concurrent; 018 019 import java.util.concurrent.Callable; 020 021 /** 022 * A listening executor service which forwards all its method calls to another 023 * listening executor service. Subclasses should override one or more methods to 024 * modify the behavior of the backing executor service as desired per the <a 025 * href="http://en.wikipedia.org/wiki/Decorator_pattern">decorator pattern</a>. 026 * 027 * @author Isaac Shum 028 * @since 10.0 029 */ 030 public abstract class ForwardingListeningExecutorService 031 extends ForwardingExecutorService implements ListeningExecutorService { 032 /** Constructor for use by subclasses. */ 033 protected ForwardingListeningExecutorService() {} 034 035 @Override 036 protected abstract ListeningExecutorService delegate(); 037 038 @Override 039 public <T> ListenableFuture<T> submit(Callable<T> task) { 040 return delegate().submit(task); 041 } 042 043 @Override 044 public ListenableFuture<?> submit(Runnable task) { 045 return delegate().submit(task); 046 } 047 048 @Override 049 public <T> ListenableFuture<T> submit(Runnable task, T result) { 050 return delegate().submit(task, result); 051 } 052 }