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 import java.util.concurrent.ExecutorService;
023
024 import org.apache.camel.Endpoint;
025 import org.apache.camel.Exchange;
026 import org.apache.camel.Expression;
027 import org.apache.camel.Processor;
028 import org.apache.camel.Producer;
029 import org.apache.camel.impl.ProducerCache;
030 import org.apache.camel.impl.ServiceSupport;
031 import org.apache.camel.processor.aggregate.AggregationStrategy;
032 import org.apache.camel.processor.aggregate.UseLatestAggregationStrategy;
033 import org.apache.camel.util.ExchangeHelper;
034 import org.apache.camel.util.ObjectHelper;
035
036 /**
037 * Implements a dynamic <a
038 * href="http://camel.apache.org/recipient-list.html">Recipient List</a>
039 * pattern where the list of actual endpoints to send a message exchange to are
040 * dependent on some dynamic expression.
041 *
042 * @version $Revision: 887262 $
043 */
044 public class RecipientList extends ServiceSupport implements Processor {
045 private ProducerCache producerCache;
046 private Expression expression;
047 private final String delimiter;
048 private boolean parallelProcessing;
049 private boolean stopOnException;
050 private ExecutorService executorService;
051 private AggregationStrategy aggregationStrategy = new UseLatestAggregationStrategy();
052
053 public RecipientList() {
054 // use comma by default as delimiter
055 this.delimiter = ",";
056 }
057
058 public RecipientList(String delimiter) {
059 this.delimiter = delimiter;
060 }
061
062 public RecipientList(Expression expression) {
063 // use comma by default as delimiter
064 this(expression, ",");
065 }
066
067 public RecipientList(Expression expression, String delimiter) {
068 ObjectHelper.notNull(expression, "expression");
069 ObjectHelper.notEmpty(delimiter, "delimiter");
070 this.expression = expression;
071 this.delimiter = delimiter;
072 }
073
074 @Override
075 public String toString() {
076 return "RecipientList[" + (expression != null ? expression : "") + "]";
077 }
078
079 public void process(Exchange exchange) throws Exception {
080 Object receipientList = expression.evaluate(exchange, Object.class);
081 sendToRecipientList(exchange, receipientList);
082 }
083
084 /**
085 * Sends the given exchange to the recipient list
086 */
087 public void sendToRecipientList(Exchange exchange, Object receipientList) throws Exception {
088 Iterator<Object> iter = ObjectHelper.createIterator(receipientList, delimiter);
089
090 List<Processor> processors = new ArrayList<Processor>();
091 while (iter.hasNext()) {
092 Object recipient = iter.next();
093 Endpoint endpoint = resolveEndpoint(exchange, recipient);
094 Producer producer = getProducerCache(exchange).getProducer(endpoint);
095 processors.add(producer);
096 }
097
098 MulticastProcessor mp = new MulticastProcessor(processors, getAggregationStrategy(), isParallelProcessing(),
099 getExecutorService(), false, isStopOnException());
100
101 // now let the multicast process the exchange
102 mp.process(exchange);
103 }
104
105 protected ProducerCache getProducerCache(Exchange exchange) throws Exception {
106 // setup producer cache as we need to use the pluggable service pool defined on camel context
107 if (producerCache == null) {
108 this.producerCache = new ProducerCache(exchange.getContext());
109 this.producerCache.start();
110 }
111 return this.producerCache;
112 }
113
114 protected Endpoint resolveEndpoint(Exchange exchange, Object recipient) {
115 // trim strings as end users might have added spaces between separators
116 if (recipient instanceof String) {
117 recipient = ((String)recipient).trim();
118 }
119 return ExchangeHelper.resolveEndpoint(exchange, recipient);
120 }
121
122 protected void doStart() throws Exception {
123 if (producerCache != null) {
124 producerCache.start();
125 }
126 }
127
128 protected void doStop() throws Exception {
129 if (producerCache != null) {
130 producerCache.stop();
131 }
132 }
133
134 public boolean isParallelProcessing() {
135 return parallelProcessing;
136 }
137
138 public void setParallelProcessing(boolean parallelProcessing) {
139 this.parallelProcessing = parallelProcessing;
140 }
141
142 public boolean isStopOnException() {
143 return stopOnException;
144 }
145
146 public void setStopOnException(boolean stopOnException) {
147 this.stopOnException = stopOnException;
148 }
149
150 public ExecutorService getExecutorService() {
151 return executorService;
152 }
153
154 public void setExecutorService(ExecutorService executorService) {
155 this.executorService = executorService;
156 }
157
158 public AggregationStrategy getAggregationStrategy() {
159 return aggregationStrategy;
160 }
161
162 public void setAggregationStrategy(AggregationStrategy aggregationStrategy) {
163 this.aggregationStrategy = aggregationStrategy;
164 }
165 }