com.sun.jbi.management.facade

Class EventNotifier

java.lang.Object

javax.management.NotificationBroadcasterSupport

com.sun.jbi.management.facade.EventNotifier

All Implemented Interfaces:

EventNotifierBase, EventNotifierMBean, EventListener, NotificationBroadcaster, NotificationEmitter, NotificationListener

public class EventNotifier
extends NotificationBroadcasterSupport
implements EventNotifierBase, EventNotifierMBean, NotificationListener

This is the DAS Event Notifier MBean that collects notifications from each instance Event Notifier MBean in the domain, and re-emits them. This allows a client to register as a notification listener with this single MBean instead of having to register with every instance Event Notifier MBean. In order for this to function correctly, this MBean keeps track of all active instances. This is accomplished in two ways. First, when this MBean is first created by the Management Runtime Service, the start() method is called to determine what instances in the domain are currently active and register with each of them as a notification listener. This is accomplished by invoking the addNotificationListener operation on the instance Event Notifier MBeans. Second, when a new instance Event Notifier MBean is registered after this MBean is already active, the new instance MBean invokes the instanceStarted operation on this MBean to inform it to register as a notification listener with the instance MBean. The instanceStarted operation in turn invokes the addNotificationListener operation on the instance MBean to complete the registration. For both cases, an entry is added to a table of instance names and MBean object names for every instance Event Notifier MBean with which this MBean is registered as a notification listener. When an instance is terminating, its Event Notifier MBean invokes the instanceStopped operation on this MBean to inform it to unregister as a notification listener with the instance MBean. The instanceStopped operation in turn invokes the removeNotificationListener operation on the instance MBean to complete the unregistration. Likewise, when the Management Runtime Service is stopping, this MBean unregisters as a notification listener from each instance Event Notifier MBean still found in the table of instance names. The entry for an instance is removed as soon as the unregistration has completed.

Author:

Mark S White

Nested Class Summary

Nested classes/interfaces inherited from interface com.sun.jbi.EventNotifierBase

EventNotifierBase.EventType, EventNotifierBase.SourceType

Field Summary

Fields inherited from interface com.sun.jbi.EventNotifierBase

COMPONENT_NAME_KEY, EVENT_TYPE_KEY, JBI_PREFIX, NOTIFICATION_CLASS_NAME, NOTIFICATION_DESCRIPTION, NOTIFICATION_TYPES, SERVICE_ASSEMBLY_NAME_KEY, SERVICE_UNIT_NAME_KEY, SOURCE_NAME_KEY, SOURCE_TYPE_KEY, TARGET_NAME_KEY

Method Summary

Methods

Modifier and Type	Method and Description
boolean	disableNotifications() This method is called to disable event notifications.
boolean	enableNotifications() This method is called to enable event notifications.
MBeanNotificationInfo[]	getNotificationInfo() Returns an array indicating, for each notification this MBean may send, the notification type, the name of the Java class of the notification, and a description of the notification.
void	handleNotification(Notification notification, Object handback) This is invoked when a JMX notification is received from an instance Event Notifier MBean with which this MBean has registered as a notification listener.
boolean	instanceStarted(String instanceName, ObjectName objectName) Inform this MBean that an instance has started and this MBean needs to register itself as a notification listener for the instance Event Notifier MBean on that instance.
boolean	instanceStopped(String instanceName, ObjectName objectName) Inform this MBean that an instance has stopped and this MBean needs to unregister itself as a notification listener for the instance Event Notifier MBean on that instance.

Methods inherited from class javax.management.NotificationBroadcasterSupport

addNotificationListener, handleNotification, removeNotificationListener, removeNotificationListener, sendNotification

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface javax.management.NotificationEmitter

removeNotificationListener

Methods inherited from interface javax.management.NotificationBroadcaster

addNotificationListener, removeNotificationListener

Method Detail

getNotificationInfo

public MBeanNotificationInfo[] getNotificationInfo()

Returns an array indicating, for each notification this MBean may send, the notification type, the name of the Java class of the notification, and a description of the notification.

Specified by:

getNotificationInfo in interface NotificationBroadcaster

Overrides:

getNotificationInfo in class NotificationBroadcasterSupport

Returns:

an array of javax.managagement.MBeanNotificationInfo objects which describe the notifications.

disableNotifications

public boolean disableNotifications()

This method is called to disable event notifications.

Specified by:

disableNotifications in interface EventNotifierMBean

Returns:

true if notifications were previously enabled, false if they were already disabled.

enableNotifications

public boolean enableNotifications()

This method is called to enable event notifications.

Specified by:

enableNotifications in interface EventNotifierMBean

Returns:

true if notifications were previously disabled, false if they were already enabled.

instanceStarted

public boolean instanceStarted(String instanceName,
                      ObjectName objectName)

Inform this MBean that an instance has started and this MBean needs to register itself as a notification listener for the instance Event Notifier MBean on that instance. This calls a method to invoke the addNotificationListener operation on the Event Notifier MBean for the specified instance using the specified JMX object name.

Specified by:

instanceStarted in interface EventNotifierMBean

Parameters:

instanceName - the name of the instance that has started.

objectName - the JMX object name of the Event Notifier MBean for the instance.

Returns:

true if registration was successful, false if not.

instanceStopped

public boolean instanceStopped(String instanceName,
                      ObjectName objectName)

Inform this MBean that an instance has stopped and this MBean needs to unregister itself as a notification listener for the instance Event Notifier MBean on that instance. This calls a method to invoke the removeNotificationListener operation on the Event Notifier MBean for the specified instance using the specified JMX object name.

Specified by:

instanceStopped in interface EventNotifierMBean

Parameters:

instanceName - the name of the instance that has stopped.

objectName - the JMX object name of the Event Notifier MBean for the instance.

Returns:

true if unregistration was successful, false if not.

handleNotification

public void handleNotification(Notification notification,
                      Object handback)

This is invoked when a JMX notification is received from an instance Event Notifier MBean with which this MBean has registered as a notification listener. If notifications are enabled, this resends the notification without modification; otherwise, this does nothing.

Specified by:

handleNotification in interface NotificationListener

Parameters:

notification - The notification object.

handback - An object reference that was used when this MBean registered as a listener with the instance Event Notifier MBean. In this case, it is the instance name.