package org.apache.helix.monitoring.mbeans;
   
   /*
    * 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.
   */
  
  import java.io.IOException;
  import java.lang.management.ManagementFactory;
  
  import javax.management.AttributeNotFoundException;
  import javax.management.InstanceNotFoundException;
  import javax.management.IntrospectionException;
  import javax.management.ListenerNotFoundException;
  import javax.management.MBeanAttributeInfo;
  import javax.management.MBeanException;
  import javax.management.MBeanInfo;
  import javax.management.MBeanServerConnection;
  import javax.management.MBeanServerDelegate;
  import javax.management.MBeanServerNotification;
  import javax.management.MalformedObjectNameException;
  import javax.management.Notification;
  import javax.management.NotificationListener;
  import javax.management.ReflectionException;
  import javax.management.relation.MBeanServerNotificationFilter;
  
  import org.apache.log4j.Logger;
  
  /*
   * TODO: this class should be in espresso common, as the only usage of it is
   * to create ingraph adaptors
   * **/
  public abstract class ClusterMBeanObserver implements NotificationListener
  {
    protected final String _domain;
    protected MBeanServerConnection _server;
    private static final Logger _logger = Logger.getLogger(ClusterMBeanObserver.class);
        
    public ClusterMBeanObserver(String domain) 
        throws InstanceNotFoundException, IOException, MalformedObjectNameException, NullPointerException
    {
      // Get a reference to the target MBeanServer
      _domain = domain;
      _server = ManagementFactory.getPlatformMBeanServer();
      MBeanServerNotificationFilter filter = new MBeanServerNotificationFilter();
      filter.enableAllObjectNames();
      _server.addNotificationListener(MBeanServerDelegate.DELEGATE_NAME, this, filter, null);
    }
    
    public void handleNotification(Notification notification, Object handback)
    {
      MBeanServerNotification mbs = (MBeanServerNotification) notification;
      if(MBeanServerNotification.REGISTRATION_NOTIFICATION.equals(mbs.getType())) 
      {
        if(mbs.getMBeanName().getDomain().equalsIgnoreCase(_domain))
        {
          _logger.info("MBean Registered, name :" + mbs.getMBeanName());
          onMBeanRegistered(_server, mbs);
        } 
      }
      else if(MBeanServerNotification.UNREGISTRATION_NOTIFICATION.equals(mbs.getType())) 
      {
        if(mbs.getMBeanName().getDomain().equalsIgnoreCase(_domain))
        {
          _logger.info("MBean Unregistered, name :" + mbs.getMBeanName());
          onMBeanUnRegistered(_server, mbs);
        }
      }
    }
    
    public void disconnect()
    {
      MBeanServerNotificationFilter filter = new MBeanServerNotificationFilter();
      try
      {
        _server.removeNotificationListener(MBeanServerDelegate.DELEGATE_NAME, this);
      }
      catch (Exception e)
      {
        _logger.error("", e);
      }
    }
    
    public abstract void onMBeanRegistered(MBeanServerConnection server, MBeanServerNotification mbsNotification);
    
   public abstract void onMBeanUnRegistered(MBeanServerConnection server, MBeanServerNotification mbsNotification);  
   
 }