001 /**
002 *
003 * Copyright 2004 Protique Ltd
004 *
005 * Licensed under the Apache License, Version 2.0 (the "License");
006 * you may not use this file except in compliance with the License.
007 * 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 **/
018
019 package org.activemq.transport.reliable;
020
021 import org.activemq.io.WireFormat;
022 import org.activemq.transport.TransportChannel;
023 import org.activemq.transport.composite.CompositeTransportChannelFactory;
024 import org.activemq.util.JMSExceptionHelper;
025
026 import javax.jms.JMSException;
027 import java.net.URI;
028 import java.net.URISyntaxException;
029 import java.util.ArrayList;
030 import java.util.Arrays;
031 import java.util.List;
032
033 /**
034 * A Reliable implementation of a TransportChannelFactory
035 *
036 * @version $Revision: 1.1.1.1 $
037 */
038 public class ReliableTransportChannelFactory extends CompositeTransportChannelFactory {
039
040 /**
041 * Create a TransportChannel
042 *
043 * @param wireFormat - the on-the-wire marshaller
044 * @param remoteLocation - location to bind to
045 * @return a reliable transport channel
046 * @throws JMSException if an error occurs
047 */
048 public TransportChannel create(WireFormat wireFormat, URI remoteLocation) throws JMSException {
049 try {
050 List uris = new ArrayList();
051 String text = parseURIs(uris, remoteLocation);
052 uris = randomizeURIs(uris);
053
054 ReliableTransportChannel channel = new ReliableTransportChannel(wireFormat, uris);
055 channel = (ReliableTransportChannel) populateProperties(channel, text);
056
057 // Using singleton pattern since this factory isn't a singleton itself
058 KeepAliveDaemon daemon = KeepAliveDaemon.getInstance();
059 daemon.addMonitoredChannel(channel);
060 daemon.start();
061
062 return channel;
063 }
064 catch (URISyntaxException e) {
065 throw JMSExceptionHelper.newJMSException("Can't parse list of URIs for: " + remoteLocation + ". Reason: "
066 + e, e);
067 }
068 }
069
070 /**
071 * @param uris - the URIs to randomize
072 * @return randomized array
073 */
074 protected List randomizeURIs(List uris) {
075 if (!uris.isEmpty()) {
076 int size = uris.size();
077 Object[] result = new Object[size];
078 SMLCGRandom random = new SMLCGRandom();
079 int startIndex = (int) (random.nextDouble() * (size + 1));
080 int count = 0;
081 for (int i = startIndex; i < size; i++) {
082 result[count++] = uris.get(i);
083 }
084 for (int i = 0; i < startIndex; i++) {
085 result[count++] = uris.get(i);
086 }
087 return new ArrayList(Arrays.asList(result));
088 }
089 return uris;
090 }
091 }