001    /**
002     * Licensed to the Apache Software Foundation (ASF) under one or more
003     * contributor license agreements.  See the NOTICE file distributed with
004     * this work for additional information regarding copyright ownership.
005     * The ASF licenses this file to You under the Apache License, Version 2.0
006     * (the "License"); you may not use this file except in compliance with
007     * the License.  You may obtain a copy of the License at
008     *
009     *      http://www.apache.org/licenses/LICENSE-2.0
010     *
011     * Unless required by applicable law or agreed to in writing, software
012     * distributed under the License is distributed on an "AS IS" BASIS,
013     * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
014     * See the License for the specific language governing permissions and
015     * limitations under the License.
016     */
017    package org.apache.camel.impl;
018    
019    import java.util.concurrent.RejectedExecutionException;
020    
021    import org.apache.camel.Endpoint;
022    import org.apache.camel.Exchange;
023    import org.apache.camel.Processor;
024    import org.apache.camel.RuntimeExchangeException;
025    import org.apache.camel.util.ServiceHelper;
026    
027    /**
028     * A simple implementation of {@link org.apache.camel.PollingConsumer} which just uses
029     * a {@link Processor}. This implementation does not support timeout based
030     * receive methods such as {@link #receive(long)}
031     *
032     * @version 
033     */
034    public class ProcessorPollingConsumer extends PollingConsumerSupport {
035        private final Processor processor;
036    
037        public ProcessorPollingConsumer(Endpoint endpoint, Processor processor) {
038            super(endpoint);
039            this.processor = processor;
040        }
041    
042        protected void doStart() throws Exception {
043            ServiceHelper.startService(processor);
044        }
045    
046        protected void doStop() throws Exception {
047            ServiceHelper.stopService(processor);
048        }
049    
050        public Exchange receive() {
051            // must be started
052            if (!isRunAllowed() || !isStarted()) {
053                throw new RejectedExecutionException(this + " is not started, but in state: " + getStatus().name());
054            }
055    
056            Exchange exchange = getEndpoint().createExchange();
057            try {
058                processor.process(exchange);
059            } catch (Exception e) {
060                throw new RuntimeExchangeException("Error while processing exchange", exchange, e);
061            }
062            return exchange;
063        }
064    
065        public Exchange receiveNoWait() {
066            return receive();
067        }
068    
069        public Exchange receive(long timeout) {
070            return receive();
071        }
072    }