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.component.seda;
018
019 import java.util.concurrent.BlockingQueue;
020 import java.util.concurrent.ExecutorService;
021 import java.util.concurrent.TimeUnit;
022
023 import org.apache.camel.Consumer;
024 import org.apache.camel.Exchange;
025 import org.apache.camel.Processor;
026 import org.apache.camel.impl.ServiceSupport;
027 import org.apache.camel.util.concurrent.ExecutorServiceHelper;
028 import org.apache.commons.logging.Log;
029 import org.apache.commons.logging.LogFactory;
030
031 /**
032 * A Consumer for the SEDA component.
033 *
034 * @version $Revision: 772598 $
035 */
036 public class SedaConsumer extends ServiceSupport implements Consumer, Runnable {
037 private static final transient Log LOG = LogFactory.getLog(SedaConsumer.class);
038
039 private SedaEndpoint endpoint;
040 private Processor processor;
041 private ExecutorService executor;
042
043 public SedaConsumer(SedaEndpoint endpoint, Processor processor) {
044 this.endpoint = endpoint;
045 this.processor = processor;
046 }
047
048 @Override
049 public String toString() {
050 return "SedaConsumer[" + endpoint.getEndpointUri() + "]";
051 }
052
053 public void run() {
054 BlockingQueue<Exchange> queue = endpoint.getQueue();
055 while (queue != null && isRunAllowed()) {
056 final Exchange exchange;
057 try {
058 exchange = queue.poll(1000, TimeUnit.MILLISECONDS);
059 } catch (InterruptedException e) {
060 LOG.debug("Sleep interrupted, are we stopping? " + (isStopping() || isStopped()));
061 continue;
062 }
063 if (exchange != null) {
064 if (isRunAllowed()) {
065 try {
066 processor.process(exchange);
067 } catch (Exception e) {
068 LOG.error("Seda queue caught: " + e, e);
069 }
070 } else {
071 LOG.warn("This consumer is stopped during polling an exchange, so putting it back on the seda queue: " + exchange);
072 try {
073 queue.put(exchange);
074 } catch (InterruptedException e) {
075 LOG.debug("Sleep interrupted, are we stopping? " + (isStopping() || isStopped()));
076 }
077 }
078 }
079 }
080 }
081
082 protected void doStart() throws Exception {
083 int poolSize = endpoint.getConcurrentConsumers();
084 executor = ExecutorServiceHelper.newFixedThreadPool(poolSize, endpoint.getEndpointUri(), true);
085 for (int i = 0; i < poolSize; i++) {
086 executor.execute(this);
087 }
088 endpoint.onStarted(this);
089 }
090
091 protected void doStop() throws Exception {
092 endpoint.onStopped(this);
093
094 executor.shutdownNow();
095 executor = null;
096 }
097
098 }