1/*
2 * Copyright (C) 2011 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
17package com.google.common.util.concurrent;
18
19import java.util.concurrent.Callable;
20
21/**
22 * A listening executor service which forwards all its method calls to another
23 * listening executor service. Subclasses should override one or more methods to
24 * modify the behavior of the backing executor service as desired per the <a
25 * href="http://en.wikipedia.org/wiki/Decorator_pattern">decorator pattern</a>.
26 *
27 * @author Isaac Shum
28 * @since 10.0
29 */
30public abstract class ForwardingListeningExecutorService
31    extends ForwardingExecutorService implements ListeningExecutorService {
32  /** Constructor for use by subclasses. */
33  protected ForwardingListeningExecutorService() {}
34
35  @Override
36  protected abstract ListeningExecutorService delegate();
37
38  @Override
39  public <T> ListenableFuture<T> submit(Callable<T> task) {
40    return delegate().submit(task);
41  }
42
43  @Override
44  public ListenableFuture<?> submit(Runnable task) {
45    return delegate().submit(task);
46  }
47
48  @Override
49  public <T> ListenableFuture<T> submit(Runnable task, T result) {
50    return delegate().submit(task, result);
51  }
52}
53