/*
* 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.felix.mosgi.jmx.agent.mx4j.server.interceptor;
import javax.management.ListenerNotFoundException;
import javax.management.Notification;
import javax.management.NotificationFilter;
import javax.management.NotificationListener;
import javax.management.ObjectName;
import org.apache.felix.mosgi.jmx.agent.mx4j.server.MBeanMetaData;
/**
* Interceptor that takes care of replacing the source of Notifications to the
* ObjectName of the NotificationBroadcaster that emitted it.
*
* @author <a href="mailto:biorn_steedom@users.sourceforge.net">Simone Bordet</a>
* @version $Revision: 1.1.1.1 $
*/
public class NotificationListenerMBeanServerInterceptor extends DefaultMBeanServerInterceptor
{
private static class ListenerWrapper implements NotificationListener
{
private final NotificationListener listener;
private final ObjectName objectName;
private ListenerWrapper(NotificationListener listener, ObjectName name)
{
this.listener = listener;
this.objectName = name;
}
public void handleNotification(Notification notification, Object handback)
{
// The JMX spec does not specify how to change the source to be the ObjectName
// of the broadcaster. If we serialize the calls to the listeners, then it's
// possible to change the source and restore it back to the old value before
// calling the next listener; but if we want to support concurrent calls
// to the listeners, this is not possible. Here I chose to support concurrent
// calls so I change the value once and I never restore it.
Object src = notification.getSource();
if (!(src instanceof ObjectName))
{
// Change the source to be the ObjectName of the notification broadcaster
// if we are not already an ObjectName (compliant with RI behaviour)
notification.setSource(objectName);
}
// Notify the real listener
NotificationListener listener = getTargetListener();
listener.handleNotification(notification, handback);
}
private NotificationListener getTargetListener()
{
return listener;
}
public int hashCode()
{
return getTargetListener().hashCode();
}
public boolean equals(Object obj)
{
if (obj == null) return false;
if (obj == this) return true;
try
{
ListenerWrapper other = (ListenerWrapper)obj;
return getTargetListener().equals(other.getTargetListener());
}
catch (ClassCastException ignored)
{
}
return false;
}
public String toString()
{
return getTargetListener().toString();
}
}
public String getType()
{
return "notificationlistener";
}
public void addNotificationListener(MBeanMetaData metadata, NotificationListener listener, NotificationFilter filter, Object handback)
{
if (isEnabled())
{
ListenerWrapper wrapper = new ListenerWrapper(listener, metadata.name);
super.addNotificationListener(metadata, wrapper, filter, handback);
}
else
{
super.addNotificationListener(metadata, listener, filter, handback);
}
}
public void removeNotificationListener(MBeanMetaData metadata, NotificationListener listener) throws ListenerNotFoundException
{
if (isEnabled())
{
ListenerWrapper wrapper = new ListenerWrapper(listener, metadata.name);
super.removeNotificationListener(metadata, wrapper);
}
else
{
super.removeNotificationListener(metadata, listener);
}
}
public void removeNotificationListener(MBeanMetaData metadata, NotificationListener listener, NotificationFilter filter, Object handback) throws ListenerNotFoundException
{
if (isEnabled())
{
ListenerWrapper wrapper = new ListenerWrapper(listener, metadata.name);
super.removeNotificationListener(metadata, wrapper, filter, handback);
}
else
{
super.removeNotificationListener(metadata, listener, filter, handback);
}
}
}