/**
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.apache.activemq.transport.discovery;
import java.net.URI;
import java.net.URISyntaxException;
import java.util.concurrent.ConcurrentHashMap;
import org.apache.activemq.command.DiscoveryEvent;
import org.apache.activemq.transport.CompositeTransport;
import org.apache.activemq.transport.TransportFilter;
import org.apache.activemq.util.ServiceStopper;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
/**
* A {@link ReliableTransportChannel} which uses a {@link DiscoveryAgent} to
* discover remote broker instances and dynamically connect to them.
*
* @version $Revision$
*/
public class DiscoveryTransport extends TransportFilter implements DiscoveryListener {
private static final Log LOG = LogFactory.getLog(DiscoveryTransport.class);
private final CompositeTransport next;
private DiscoveryAgent discoveryAgent;
private final ConcurrentHashMap<String, URI> serviceURIs = new ConcurrentHashMap<String, URI>();
public DiscoveryTransport(CompositeTransport next) {
super(next);
this.next = next;
}
public void start() throws Exception {
if (discoveryAgent == null) {
throw new IllegalStateException("discoveryAgent not configured");
}
// lets pass into the agent the broker name and connection details
discoveryAgent.setDiscoveryListener(this);
discoveryAgent.start();
next.start();
}
public void stop() throws Exception {
ServiceStopper ss = new ServiceStopper();
ss.stop(discoveryAgent);
ss.stop(next);
ss.throwFirstException();
}
public void onServiceAdd(DiscoveryEvent event) {
String url = event.getServiceName();
if (url != null) {
try {
URI uri = new URI(url);
serviceURIs.put(event.getServiceName(), uri);
LOG.info("Adding new broker connection URL: " + uri);
next.add(new URI[] {uri});
} catch (URISyntaxException e) {
LOG.warn("Could not connect to remote URI: " + url + " due to bad URI syntax: " + e, e);
}
}
}
public void onServiceRemove(DiscoveryEvent event) {
URI uri = serviceURIs.get(event.getServiceName());
if (uri != null) {
next.remove(new URI[] {uri});
}
}
public DiscoveryAgent getDiscoveryAgent() {
return discoveryAgent;
}
public void setDiscoveryAgent(DiscoveryAgent discoveryAgent) {
this.discoveryAgent = discoveryAgent;
}
}