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 package org.activemq.transport;
019 import java.util.Iterator;
020 import EDU.oswego.cs.dl.util.concurrent.*;
021 import org.apache.commons.logging.Log;
022 import org.apache.commons.logging.LogFactory;
023
024 /**
025 * A useful base class for {@link DiscoveryAgent} implementations
026 *
027 * @version $Revision: 1.1.1.1 $
028 */
029 public abstract class DiscoveryAgentSupport implements DiscoveryAgent {
030 private static final transient Log log = LogFactory.getLog(DiscoveryAgentSupport.class);
031
032 protected CopyOnWriteArrayList listeners = new CopyOnWriteArrayList();
033
034 /**
035 * Add a discovery listener
036 * @param listener
037 */
038 public void addDiscoveryListener(DiscoveryListener listener){
039 listeners.add(listener);
040 }
041
042 /**
043 * remove a discovery listener
044 * @param listener
045 */
046 public void removeDiscoveryListener(DiscoveryListener listener){
047 listeners.remove(listener);
048 }
049
050 protected void fireAddService(DiscoveryEvent event){
051 for(Iterator i = listeners.iterator(); i.hasNext();){
052 DiscoveryListener l = (DiscoveryListener)i.next();
053 if (log.isDebugEnabled()) {
054 log.debug("on Add service: " + event);
055 }
056 l.addService(event);
057 }
058 }
059
060 protected void fireRemoveService(DiscoveryEvent event){
061 for(Iterator i = listeners.iterator(); i.hasNext();){
062 DiscoveryListener l = (DiscoveryListener)i.next();
063 if (log.isDebugEnabled()) {
064 log.debug("on Remove service: " + event);
065 }
066 l.removeService(event);
067 }
068 }
069
070 }