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    /**
023     * A {@link Service} that forwards all method calls to another service.
024     *
025     * @author Chris Nokleberg
026     * @since 1.0
027     */
028    @Beta
029    public abstract class ForwardingService extends ForwardingObject
030        implements Service {
031    
032      /** Constructor for use by subclasses. */
033      protected ForwardingService() {}
034    
035      @Override protected abstract Service delegate();
036    
037      @Override public ListenableFuture<State> start() {
038        return delegate().start();
039      }
040    
041      @Override public State state() {
042        return delegate().state();
043      }
044    
045      @Override public ListenableFuture<State> stop() {
046        return delegate().stop();
047      }
048    
049      @Override public State startAndWait() {
050        return delegate().startAndWait();
051      }
052    
053      @Override public State stopAndWait() {
054        return delegate().stopAndWait();
055      }
056    
057      @Override public boolean isRunning() {
058        return delegate().isRunning();
059      }
060    
061      /**
062       * A sensible default implementation of {@link #startAndWait()}, in terms of
063       * {@link #start}. If you override {@link #start}, you may wish to override
064       * {@link #startAndWait()} to forward to this implementation.
065       * @since 9.0
066       */
067      protected State standardStartAndWait() {
068        return Futures.getUnchecked(start());
069      }
070    
071      /**
072       * A sensible default implementation of {@link #stopAndWait()}, in terms of
073       * {@link #stop}. If you override {@link #stop}, you may wish to override
074       * {@link #stopAndWait()} to forward to this implementation.
075       * @since 9.0
076       */
077      protected State standardStopAndWait() {
078        return Futures.getUnchecked(stop());
079      }
080    }