com.gemstone.gemfire.management.internal.NotificationHub Maven / Gradle / Ivy
/*
* Copyright (c) 2010-2015 Pivotal Software, Inc. All rights reserved.
*
* Licensed 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. See accompanying
* LICENSE file.
*/
package com.gemstone.gemfire.management.internal;
import java.util.HashMap;
import java.util.Map;
import javax.management.InstanceNotFoundException;
import javax.management.ListenerNotFoundException;
import javax.management.MBeanServer;
import javax.management.Notification;
import javax.management.NotificationListener;
import javax.management.ObjectName;
import com.gemstone.gemfire.distributed.internal.InternalDistributedSystem;
import com.gemstone.gemfire.i18n.LogWriterI18n;
import com.gemstone.gemfire.management.ManagementException;
/**
* This class acts as a central point hub for collecting all notifications
* originated from VM and sending across to Managing Node
*
* @author rishim
*
*/
public class NotificationHub {
/**
* logger
*/
private LogWriterI18n logger;
/**
* This is a single window to manipulate region resources for management
*/
protected ManagementResourceRepo repo;
/**
* Platform MBean Server
*/
private MBeanServer mbeanServer = MBeanJMXAdapter.mbeanServer;
private Map listenerObjectMap;
/** Member Name **/
private String memberSource;
/**
* public constructor
*
* @param repo
* Resource repo for this member
*/
public NotificationHub(ManagementResourceRepo repo) {
this.repo = repo;
logger = InternalDistributedSystem.getLoggerI18n();
this.listenerObjectMap = new HashMap();
memberSource = MBeanJMXAdapter.getMemberNameOrId(InternalDistributedSystem
.getConnectedInstance().getDistributedMember());
}
/**
* Adds a NotificationHubListener
*
* @param objectName
*/
public void addHubNotificationListener(String memberName,
ObjectName objectName) {
try {
synchronized (listenerObjectMap) {
NotificationHubListener listener = listenerObjectMap.get(objectName);
if (listener == null) {
listener = new NotificationHubListener(objectName);
listener.incNumCounter();
mbeanServer.addNotificationListener(objectName, listener, null, null);
listenerObjectMap.put(objectName, listener);
} else {
listener.incNumCounter();
}
}
} catch (InstanceNotFoundException e) {
throw new ManagementException(e);
}
}
/**
* Removes a NotificationHubListener
*
* @param objectName
*/
public void removeHubNotificationListener(String memberName, ObjectName objectName) {
try {
synchronized (listenerObjectMap) {
if (listenerObjectMap.get(objectName) != null) {
NotificationHubListener listener = listenerObjectMap.get(objectName);
if (listener.decNumCounter() == 0) {
listenerObjectMap.remove(objectName);
// The MBean might have been un registered if the resource is
// removed from cache.
// The below method is to ensure clean up of user defined MBeans
mbeanServer.removeNotificationListener(objectName, listener);
}
}
}
} catch (ListenerNotFoundException e) {
// No op
} catch (InstanceNotFoundException e) {
// No op
}
}
/**
* This method is basically to cleanup resources which might cause leaks if
* the same VM is used again for cache creation.
*/
public void cleanUpListeners() {
synchronized (listenerObjectMap) {
for (ObjectName objectName : listenerObjectMap.keySet()) {
NotificationHubListener listener = listenerObjectMap.get(objectName);
if (listener != null) {
try {
mbeanServer.removeNotificationListener(objectName, listener);
} catch (ListenerNotFoundException e) {
// Do nothing. Already have been un-registered ( For listeners which
// are on other MBeans apart from MemberMXBean)
} catch (InstanceNotFoundException e) {
// Do nothing. Already have been un-registered ( For listeners which
// are on other MBeans apart from MemberMXBean)
}
}
}
}
listenerObjectMap.clear();
}
public Map getListenerObjectMap() {
return this.listenerObjectMap;
}
/**
* This class is the managed node counterpart to listen to notifications from
* MBeans for which it is resistered
*
* @author rishim
*
*/
public class NotificationHubListener implements NotificationListener {
/**
* MBean for which this listener is added
*/
private ObjectName name;
/**
* Counter to indicate how many listener are attached to this MBean
*/
private int numCounter = 0;
protected NotificationHubListener(ObjectName name) {
this.name = name;
}
public int incNumCounter() {
return ++numCounter;
}
public int decNumCounter() {
return --numCounter;
}
public int getNumCounter(){
return this.numCounter;
}
@Override
public void handleNotification(Notification notification, Object handback) {
NotificationKey key = new NotificationKey(name);
notification.setUserData(memberSource);
repo.putEntryInLocalNotificationRegion(key, notification);
}
}
}