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.processor;
018
019 import java.util.ArrayList;
020 import java.util.Iterator;
021 import java.util.List;
022
023 import org.apache.camel.Endpoint;
024 import org.apache.camel.Exchange;
025 import org.apache.camel.Expression;
026 import org.apache.camel.Processor;
027 import org.apache.camel.Producer;
028 import org.apache.camel.impl.ProducerCache;
029 import org.apache.camel.impl.ServiceSupport;
030 import org.apache.camel.processor.aggregate.UseLatestAggregationStrategy;
031 import org.apache.camel.util.ExchangeHelper;
032 import org.apache.camel.util.ObjectHelper;
033 import static org.apache.camel.util.ObjectHelper.notNull;
034
035 /**
036 * Implements a dynamic <a
037 * href="http://activemq.apache.org/camel/recipient-list.html">Recipient List</a>
038 * pattern where the list of actual endpoints to send a message exchange to are
039 * dependent on some dynamic expression.
040 *
041 * @version $Revision: 734353 $
042 */
043 public class RecipientList extends ServiceSupport implements Processor {
044 private final Expression<Exchange> expression;
045 private ProducerCache<Exchange> producerCache = new ProducerCache<Exchange>();
046
047 public RecipientList(Expression<Exchange> expression) {
048 notNull(expression, "expression");
049 this.expression = expression;
050 }
051
052 @Override
053 public String toString() {
054 return "RecipientList[" + expression + "]";
055 }
056
057 public void process(Exchange exchange) throws Exception {
058 Object receipientList = expression.evaluate(exchange);
059 sendToRecipientList(exchange, receipientList);
060 }
061
062 /**
063 * Sends the given exchange to the recipient list
064 */
065 public void sendToRecipientList(Exchange exchange, Object receipientList) throws Exception {
066 Iterator iter = ObjectHelper.createIterator(receipientList);
067 List<Processor> processors = new ArrayList<Processor>();
068 while (iter.hasNext()) {
069 Object recipient = iter.next();
070 Endpoint<Exchange> endpoint = resolveEndpoint(exchange, recipient);
071 Producer<Exchange> producer = producerCache.getProducer(endpoint);
072 processors.add(producer);
073 }
074 MulticastProcessor mp = new MulticastProcessor(processors, new UseLatestAggregationStrategy());
075 mp.process(exchange);
076 }
077
078 protected Endpoint<Exchange> resolveEndpoint(Exchange exchange, Object recipient) {
079 // trim strings as end users might have added spaces between separators
080 if (recipient instanceof String) {
081 recipient = ((String)recipient).trim();
082 }
083 return ExchangeHelper.resolveEndpoint(exchange, recipient);
084 }
085
086 protected void doStop() throws Exception {
087 producerCache.stop();
088 }
089
090 protected void doStart() throws Exception {
091 }
092 }