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.vm;
018
019 import java.util.HashMap;
020 import java.util.Map;
021 import java.util.concurrent.BlockingQueue;
022
023 import org.apache.camel.Endpoint;
024 import org.apache.camel.Exchange;
025 import org.apache.camel.component.seda.SedaComponent;
026 import org.apache.camel.component.seda.SedaEndpoint;
027
028 /**
029 * An implementation of the <a href="http://activemq.apache.org/camel/vm.html">VM components</a>
030 * for asynchronous SEDA exchanges on a {@link BlockingQueue} within the classloader tree containing
031 * the camel-core.jar. i.e. to handle communicating across CamelContext instances and possibly across
032 * web application contexts, providing that camel-core.jar is on the system classpath.
033 *
034 * @version $Revision: 1.1 $
035 */
036 public class VmComponent<E extends Exchange> extends SedaComponent<E> {
037 protected static Map<String, BlockingQueue<Exchange>> queues = new HashMap<String, BlockingQueue<Exchange>>();
038
039 @Override
040 protected Endpoint<E> createEndpoint(String uri, String remaining, Map parameters) throws Exception {
041 BlockingQueue<E> blockingQueue = (BlockingQueue<E>) getBlockingQueue(uri);
042 return new SedaEndpoint<E>(uri, this, blockingQueue);
043 }
044
045 protected BlockingQueue<Exchange> getBlockingQueue(String uri) {
046 synchronized (queues) {
047 BlockingQueue<Exchange> answer = queues.get(uri);
048 if (answer == null) {
049 answer = (BlockingQueue<Exchange>) createQueue();
050 queues.put(uri, answer);
051 }
052 return answer;
053 }
054 }
055 }