Class MBeanServerNotification

Represents a notification emitted by the MBean Server through the MBeanServerDelegate MBean. The MBean Server emits the following types of notifications: MBean registration, MBean unregistration.

To receive MBeanServerNotifications, you need to register a listener with the MBeanServerDelegate MBean that represents the MBeanServer. The ObjectName of the MBeanServerDelegate is MBeanServerDelegate.DELEGATE_NAME, which is JMImplementation:type=MBeanServerDelegate.

The following code prints a message every time an MBean is registered or unregistered in the MBean Server mbeanServer:

private static final NotificationListener printListener = new NotificationListener() {
     public void handleNotification(Notification n, Object handback) {
         if (!(n instanceof MBeanServerNotification)) {
             System.out.println("Ignored notification of class " + n.getClass().getName());
             return;
         }
         MBeanServerNotification mbsn = (MBeanServerNotification) n;
         String what;
         if (n.getType().equals(MBeanServerNotification.REGISTRATION_NOTIFICATION))
             what = "MBean registered";
         else if (n.getType().equals(MBeanServerNotification.UNREGISTRATION_NOTIFICATION))
             what = "MBean unregistered";
         else
             what = "Unknown type " + n.getType();
         System.out.println("Received MBean Server notification: " + what + ": " +
                 mbsn.getMBeanName());
     }
 };

 ...
     mbeanServer.addNotificationListener(
             MBeanServerDelegate.DELEGATE_NAME, printListener, null, null);

An MBean which is not an MBeanServerDelegate may also emit MBeanServerNotifications. In particular, there is a convention for MBeans to emit an MBeanServerNotification for a group of MBeans.

An MBeanServerNotification emitted to denote the registration or unregistration of a group of MBeans has the following characteristics:

• Its notification type is "JMX.mbean.registered.group" or "JMX.mbean.unregistered.group", which can also be written REGISTRATION_NOTIFICATION+ ".group" or UNREGISTRATION_NOTIFICATION+ ".group".
• Its MBean name is an ObjectName pattern that selects the set (or a superset) of the MBeans being registered or unregistered
• Its user data can optionally be set to an array of ObjectNames containing the names of all MBeans being registered or unregistered.

MBeans which emit these group registration/unregistration notifications will declare them in their MBeanNotificationInfo.