001 /**
002 *
003 * Licensed to the Apache Software Foundation (ASF) under one or more
004 * contributor license agreements. See the NOTICE file distributed with
005 * this work for additional information regarding copyright ownership.
006 * The ASF licenses this file to You under the Apache License, Version 2.0
007 * (the "License"); you may not use this file except in compliance with
008 * the License. You may obtain a copy of the License at
009 *
010 * http://www.apache.org/licenses/LICENSE-2.0
011 *
012 * Unless required by applicable law or agreed to in writing, software
013 * distributed under the License is distributed on an "AS IS" BASIS,
014 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
015 * See the License for the specific language governing permissions and
016 * limitations under the License.
017 */
018 package org.apache.camel.processor;
019
020 import org.apache.camel.Endpoint;
021 import org.apache.camel.Exchange;
022 import org.apache.camel.Expression;
023 import org.apache.camel.Processor;
024 import org.apache.camel.converter.ObjectConverter;
025 import org.apache.camel.impl.ServiceSupport;
026 import org.apache.camel.util.ExchangeHelper;
027 import static org.apache.camel.util.ObjectHelper.notNull;
028 import org.apache.camel.util.ProducerCache;
029
030 import java.util.Iterator;
031
032 /**
033 * Implements a dynamic <a href="http://activemq.apache.org/camel/recipient-list.html">Recipient List</a> pattern
034 * where the list of actual endpoints to send a message exchange to are dependent on some dynamic expression.
035 *
036 * @version $Revision: 534145 $
037 */
038 public class RecipientList extends ServiceSupport implements Processor {
039 private final Expression<Exchange> expression;
040 private ProducerCache<Exchange> producerCache = new ProducerCache<Exchange>();
041
042 public RecipientList(Expression<Exchange> expression) {
043 notNull(expression, "expression");
044 this.expression = expression;
045 }
046
047 @Override
048 public String toString() {
049 return "RecipientList[" + expression + "]";
050 }
051
052 public void process(Exchange exchange) throws Exception {
053 Object receipientList = expression.evaluate(exchange);
054 Iterator iter = ObjectConverter.iterator(receipientList);
055 while (iter.hasNext()) {
056 Object recipient = iter.next();
057 Endpoint<Exchange> endpoint = resolveEndpoint(exchange, recipient);
058 producerCache.getProducer(endpoint).process(exchange);
059 }
060 }
061
062 protected Endpoint<Exchange> resolveEndpoint(Exchange exchange, Object recipient) {
063 return ExchangeHelper.resolveEndpoint(exchange, recipient);
064 }
065
066 protected void doStop() throws Exception {
067 producerCache.stop();
068 }
069
070 protected void doStart() throws Exception {
071 }
072 }