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    
017    package com.google.common.util.concurrent;
018    
019    import com.google.common.annotations.Beta;
020    import com.google.common.collect.ForwardingObject;
021    
022    import 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
031    public abstract class ForwardingService extends ForwardingObject
032        implements Service {
033    
034      /** Constructor for use by subclasses. */
035      protected ForwardingService() {}
036    
037      
038      @Override
039      protected abstract Service delegate();
040    
041      public ListenableFuture<State> start() {
042        return delegate().start();
043      }
044    
045      public State state() {
046        return delegate().state();
047      }
048    
049      public ListenableFuture<State> stop() {
050        return delegate().stop();
051      }
052    
053      public State startAndWait() {
054        return delegate().startAndWait();
055      }
056    
057      public State stopAndWait() {
058        return delegate().stopAndWait();
059      }
060    
061      public boolean isRunning() {
062        return delegate().isRunning();
063      }
064    
065      public void addListener(Listener listener, Executor executor) {
066        delegate().addListener(listener, executor);
067      }
068    
069      /**
070       * A sensible default implementation of {@link #startAndWait()}, in terms of
071       * {@link #start}. If you override {@link #start}, you may wish to override
072       * {@link #startAndWait()} to forward to this implementation.
073       * @since 9.0
074       */
075      protected State standardStartAndWait() {
076        return Futures.getUnchecked(start());
077      }
078    
079      /**
080       * A sensible default implementation of {@link #stopAndWait()}, in terms of
081       * {@link #stop}. If you override {@link #stop}, you may wish to override
082       * {@link #stopAndWait()} to forward to this implementation.
083       * @since 9.0
084       */
085      protected State standardStopAndWait() {
086        return Futures.getUnchecked(stop());
087      }
088    }