001/* 002 * Copyright (C) 2009 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 017package com.google.common.util.concurrent; 018 019import com.google.common.annotations.Beta; 020import com.google.common.collect.ForwardingObject; 021 022import java.util.concurrent.Executor; 023 024/** 025 * A {@link Service} that forwards all method calls to another service. 026 * 027 * @author Chris Nokleberg 028 * @since 1.0 029 */ 030@Beta 031public abstract class ForwardingService extends ForwardingObject 032 implements Service { 033 034 /** Constructor for use by subclasses. */ 035 protected ForwardingService() {} 036 037 @Override protected abstract Service delegate(); 038 039 @Override public ListenableFuture<State> start() { 040 return delegate().start(); 041 } 042 043 @Override public State state() { 044 return delegate().state(); 045 } 046 047 @Override public ListenableFuture<State> stop() { 048 return delegate().stop(); 049 } 050 051 @Override public State startAndWait() { 052 return delegate().startAndWait(); 053 } 054 055 @Override public State stopAndWait() { 056 return delegate().stopAndWait(); 057 } 058 059 @Override public boolean isRunning() { 060 return delegate().isRunning(); 061 } 062 063 /** 064 * @since 13.0 065 */ 066 @Override public void addListener(Listener listener, Executor executor) { 067 delegate().addListener(listener, executor); 068 } 069 070 /** 071 * @since 14.0 072 */ 073 @Override public Throwable failureCause() { 074 return delegate().failureCause(); 075 } 076 077 /** 078 * A sensible default implementation of {@link #startAndWait()}, in terms of 079 * {@link #start}. If you override {@link #start}, you may wish to override 080 * {@link #startAndWait()} to forward to this implementation. 081 * @since 9.0 082 */ 083 protected State standardStartAndWait() { 084 return Futures.getUnchecked(start()); 085 } 086 087 /** 088 * A sensible default implementation of {@link #stopAndWait()}, in terms of 089 * {@link #stop}. If you override {@link #stop}, you may wish to override 090 * {@link #stopAndWait()} to forward to this implementation. 091 * @since 9.0 092 */ 093 protected State standardStopAndWait() { 094 return Futures.getUnchecked(stop()); 095 } 096}