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.Map;
020
021 import org.apache.camel.CamelContext;
022 import org.apache.camel.Endpoint;
023 import org.apache.camel.Exchange;
024 import org.apache.camel.FailedToCreateConsumerException;
025 import org.apache.camel.IsSingleton;
026 import org.apache.camel.PollingConsumer;
027 import org.apache.camel.util.CamelContextHelper;
028 import org.apache.camel.util.LRUCache;
029 import org.apache.camel.util.ServiceHelper;
030 import org.apache.commons.logging.Log;
031 import org.apache.commons.logging.LogFactory;
032
033 /**
034 * Cache containing created {@link org.apache.camel.Consumer}.
035 *
036 * @version $Revision: 937935 $
037 */
038 public class ConsumerCache extends ServiceSupport {
039 private static final transient Log LOG = LogFactory.getLog(ConsumerCache.class);
040 private final CamelContext camelContext;
041 private final Map<String, PollingConsumer> consumers;
042
043 public ConsumerCache(CamelContext camelContext) {
044 this(camelContext, CamelContextHelper.getMaximumCachePoolSize(camelContext));
045 }
046
047 public ConsumerCache(CamelContext camelContext, int maximumCacheSize) {
048 this(camelContext, new LRUCache<String, PollingConsumer>(maximumCacheSize));
049 }
050
051 public ConsumerCache(CamelContext camelContext, Map<String, PollingConsumer> cache) {
052 this.camelContext = camelContext;
053 this.consumers = cache;
054 }
055
056 public synchronized PollingConsumer getConsumer(Endpoint endpoint) {
057 String key = endpoint.getEndpointUri();
058 PollingConsumer answer = consumers.get(key);
059 if (answer == null) {
060 try {
061 answer = endpoint.createPollingConsumer();
062 answer.start();
063 } catch (Exception e) {
064 throw new FailedToCreateConsumerException(endpoint, e);
065 }
066
067 boolean singleton = true;
068 if (answer instanceof IsSingleton) {
069 singleton = ((IsSingleton) answer).isSingleton();
070 }
071
072 if (singleton) {
073 if (LOG.isDebugEnabled()) {
074 LOG.debug("Adding to consumer cache with key: " + endpoint + " for consumer: " + answer);
075 }
076 consumers.put(key, answer);
077 } else {
078 if (LOG.isDebugEnabled()) {
079 LOG.debug("Consumer for endpoint: " + key + " is not singleton and thus not added to consumer cache");
080 }
081 }
082 }
083 return answer;
084 }
085
086 public Exchange receive(Endpoint endpoint) {
087 if (LOG.isDebugEnabled()) {
088 LOG.debug("<<<< " + endpoint);
089 }
090
091 PollingConsumer consumer = getConsumer(endpoint);
092 return consumer.receive();
093 }
094
095 public Exchange receive(Endpoint endpoint, long timeout) {
096 if (LOG.isDebugEnabled()) {
097 LOG.debug("<<<< " + endpoint);
098 }
099
100 PollingConsumer consumer = getConsumer(endpoint);
101 return consumer.receive(timeout);
102 }
103
104 public Exchange receiveNoWait(Endpoint endpoint) {
105 if (LOG.isDebugEnabled()) {
106 LOG.debug("<<<< " + endpoint);
107 }
108
109 PollingConsumer consumer = getConsumer(endpoint);
110 return consumer.receiveNoWait();
111 }
112
113 public CamelContext getCamelContext() {
114 return camelContext;
115 }
116
117 protected void doStart() throws Exception {
118 ServiceHelper.startServices(consumers);
119 }
120
121 protected void doStop() throws Exception {
122 ServiceHelper.stopServices(consumers);
123 consumers.clear();
124 }
125
126 /**
127 * Returns the current size of the consumer cache
128 *
129 * @return the current size
130 */
131 int size() {
132 return consumers.size();
133 }
134
135 }