Please note that this documentation is not final and is subject to change.

javax.management.event
Class EventClientDelegate

java.lang.Object
  javax.management.event.EventClientDelegate

All Implemented Interfaces:

EventClientDelegateMBean

public class EventClientDelegate
extends Object
implements EventClientDelegateMBean

This is the default implementation of the MBean EventClientDelegateMBean.

Field Summary

Modifier and Type	Field and Description

Fields inherited from interface javax.management.event.EventClientDelegateMBean

EVENT_CLIENT_LISTENER_ID, OBJECT_NAME, OBJECT_NAME_STRING

Method Summary

Modifier and Type	Method and Description
String	addClient(String className, Object[] params, String[] sig) Adds a new client to the EventClientDelegateMBean with a user-specified EventForwarder to forward notifications to the client.
String	addClient(String className, ObjectName classLoader, Object[] params, String[] sig) Adds a new client to the EventClientDelegateMBean with a user-specified EventForwarder to forward notifications to the client.
Integer	addListener(String clientId, ObjectName name, NotificationFilter filter) Adds a listener to receive notifications from an MBean and returns a non-negative integer as the identifier of the listener.
Integer	addSubscriber(String clientId, ObjectName name, NotificationFilter filter) Subscribes a listener to receive notifications from an MBean or a set of MBeans represented by an ObjectName pattern.
NotificationResult	fetchNotifications(String clientId, long startSequenceNumber, int maxNotifs, long timeout) Called by a client to fetch notifications that are to be sent to its listeners.
static EventClientDelegate	getEventClientDelegate(MBeanServer server) Returns an EventClientDelegate instance for the given MBeanServer.
Integer[]	getListenerIds(String clientId) Returns the identifiers of listeners added or subscribed to with the specified client identifier.
static EventClientDelegateMBean	getProxy(MBeanServerConnection conn) Returns a proxy of the default EventClientDelegateMBean.
long	lease(String clientId, long timeout) An EventClient calls this method to keep its clientId alive in this MBean.
static MBeanServerForwarder	newForwarder(MBeanServer nextMBS, MBeanServer loopMBS) Create a new MBeanServerForwarder that simulates the existence of an EventClientDelegateMBean with the default name.
void	removeClient(String clientId) Removes an added client.
void	removeListenerOrSubscriber(String clientId, Integer listenerId) Removes a listener, to stop receiving notifications.

Methods inherited from class java.lang.Object

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

Method Detail

getEventClientDelegate

public static EventClientDelegate getEventClientDelegate(MBeanServer server)

Returns an EventClientDelegate instance for the given MBeanServer. Calling this method more than once with the same server argument may return the same object or a different object each time. See EventClientDelegateMBean for an example use of this method.

Parameters:

server - An MBean server instance to work with.

Returns:

An EventClientDelegate instance.

Throws:

NullPointerException - If server is null.

newForwarder

public static MBeanServerForwarder newForwarder(MBeanServer nextMBS,
                                                MBeanServer loopMBS)

Create a new MBeanServerForwarder that simulates the existence of an EventClientDelegateMBean with the default name. This forwarder intercepts MBean requests that are targeted for that MBean and handles them itself. All other requests are forwarded to the next element in the forwarder chain.

Parameters:

nextMBS - the next MBeanServer in the chain of forwarders, which might be another MBeanServerForwarder or a plain MBeanServer. This is the object to which MBeanServer requests that do not concern the EventClientDelegateMBean are sent. It will be the value of getMBeanServer() on the returned object, and can be changed with setMBeanServer. It can be null but must be set to a non-null value before any MBeanServer requests arrive.

loopMBS - the MBeanServer to which requests from the EventClientDelegateMBean should be sent. For example, when you invoke the addListener operation on the EventClientDelegateMBean, it will result in a call to addNotificationListener on this object. If this parameter is null, then these requests will be sent to the newly-created MBeanServerForwarder. Usually the parameter will either be null or will be the result of getSystemMBeanServerForwarder() for the connector server in which this forwarder will be installed.

Returns:

a new MBeanServerForwarder that simulates the existence of an EventClientDelegateMBean.

See Also:

JMXConnectorServer.installStandardForwarders(java.util.Map)

getProxy

public static EventClientDelegateMBean getProxy(MBeanServerConnection conn)

Returns a proxy of the default EventClientDelegateMBean.

Parameters:

conn - An MBeanServerConnection to work with.

addClient

public String addClient(String className,
                        Object[] params,
                        String[] sig)
                 throws MBeanException

Description copied from interface: EventClientDelegateMBean

Adds a new client to the EventClientDelegateMBean with a user-specified EventForwarder to forward notifications to the client. The EventForwarder is created by calling MBeanServer.instantiate(String, Object[], String[]).

Specified by:

addClient in interface EventClientDelegateMBean

Parameters:

className - The class name used to create an EventForwarder.

params - An array containing the parameters of the constructor to be invoked.

sig - An array containing the signature of the constructor to be invoked

Returns:

A client identifier.

Throws:

MBeanException - An exception thrown when creating the user specified EventForwarder.

addClient

public String addClient(String className,
                        ObjectName classLoader,
                        Object[] params,
                        String[] sig)
                 throws MBeanException

Description copied from interface: EventClientDelegateMBean

Adds a new client to the EventClientDelegateMBean with a user-specified EventForwarder to forward notifications to the client. The EventForwarder is created by calling MBeanServer.instantiate(String, ObjectName, Object[], String[]). A user-specified class loader is used to create this EventForwarder.

Specified by:

addClient in interface EventClientDelegateMBean

Parameters:

className - The class name used to create an EventForwarder.

classLoader - An ObjectName registered as a ClassLoader MBean.

params - An array containing the parameters of the constructor to be invoked.

sig - An array containing the signature of the constructor to be invoked

Returns:

A client identifier.

Throws:

MBeanException - An exception thrown when creating the user specified EventForwarder.

getListenerIds

public Integer[] getListenerIds(String clientId)
                         throws IOException,
                                EventClientNotFoundException

Description copied from interface: EventClientDelegateMBean

Returns the identifiers of listeners added or subscribed to with the specified client identifier.

If no listener is currently registered with the client, an empty array is returned.

Specified by:

getListenerIds in interface EventClientDelegateMBean

Parameters:

clientId - The client identifier with which the listeners are added or subscribed to.

Returns:

An array of listener identifiers.

Throws:

IOException - Reserved for a remote call to throw on the client side.

EventClientNotFoundException - If the clientId is not found.

addListener

public Integer addListener(String clientId,
                           ObjectName name,
                           NotificationFilter filter)
                    throws EventClientNotFoundException,
                           InstanceNotFoundException

Adds a listener to receive notifications from an MBean and returns a non-negative integer as the identifier of the listener.

This method is called by an EventClient to implement the method EventClient.addNotificationListener(ObjectName, NotificationListener, NotificationFilter, Object).

The execution of this method includes a call to MBeanServer.addNotificationListener(ObjectName, NotificationListener, NotificationFilter, Object).

Specified by:

addListener in interface EventClientDelegateMBean

Parameters:

clientId - The client identifier with which the listener is added.

name - The name of the MBean onto which the listener should be added.

filter - The filter object. If filter is null, no filtering will be performed before handling notifications.

Returns:

A listener identifier.

Throws:

EventClientNotFoundException - Thrown if the clientId is not found.

InstanceNotFoundException - Thrown if the MBean is not found.

removeListenerOrSubscriber

public void removeListenerOrSubscriber(String clientId,
                                       Integer listenerId)
                                throws InstanceNotFoundException,
                                       ListenerNotFoundException,
                                       EventClientNotFoundException,
                                       IOException

Removes a listener, to stop receiving notifications.

This method is called by an EventClient to execute its methods EventClient.removeNotificationListener(ObjectName, NotificationListener, NotificationFilter, Object), EventClient.removeNotificationListener(ObjectName, NotificationListener), and EventClient.unsubscribe(javax.management.ObjectName, javax.management.NotificationListener).

The execution of this method can include call to MBeanServer.removeNotificationListener(ObjectName, NotificationListener, NotificationFilter, Object).

Specified by:

removeListenerOrSubscriber in interface EventClientDelegateMBean

Parameters:

clientId - The client identifier with which the listener was added.

listenerId - The listener identifier to be removed. This must be an identifier returned by a previous addListener or addSubscriber call.

Throws:

InstanceNotFoundException - if the MBean on which the listener was added no longer exists.

ListenerNotFoundException - if there is no listener with the given listenerId.

EventClientNotFoundException - if the clientId is not found.

IOException - Reserved for a remote call to throw on the client side.

addSubscriber

public Integer addSubscriber(String clientId,
                             ObjectName name,
                             NotificationFilter filter)
                      throws EventClientNotFoundException,
                             IOException

Subscribes a listener to receive notifications from an MBean or a set of MBeans represented by an ObjectName pattern. (It is not an error if no MBeans match the pattern at the time this method is called.)

Returns a non-negative integer as the identifier of the listener.

This method is called by an EventClient to execute its method EventClient.subscribe(ObjectName, NotificationListener, NotificationFilter, Object).

The execution of this method includes a call to MBeanServer.addNotificationListener(ObjectName, NotificationListener, NotificationFilter, Object) for every MBean matching name. If name is an ObjectName pattern, then the execution of this method will include a call to MBeanServer.queryNames(javax.management.ObjectName, javax.management.QueryExp).

Specified by:

addSubscriber in interface EventClientDelegateMBean

Parameters:

clientId - The remote client's identifier.

name - The name of an MBean or an ObjectName pattern representing a set of MBeans to which the listener should listen.

filter - The filter object. If filter is null, no filtering will be performed before notifications are handled.

Returns:

A listener identifier.

Throws:

EventClientNotFoundException - If the client ID is not found.

IOException - Reserved for a remote client to throw if an I/O error occurs.

See Also:

EventConsumer.subscribe(ObjectName, NotificationListener, NotificationFilter,Object), EventClientDelegateMBean.removeListenerOrSubscriber(String, Integer)

fetchNotifications

public NotificationResult fetchNotifications(String clientId,
                                             long startSequenceNumber,
                                             int maxNotifs,
                                             long timeout)
                                      throws EventClientNotFoundException

Description copied from interface: EventClientDelegateMBean

Called by a client to fetch notifications that are to be sent to its listeners.

Specified by:

fetchNotifications in interface EventClientDelegateMBean

Parameters:

clientId - The client's identifier.

startSequenceNumber - The first sequence number to consider.

maxNotifs - The maximum number of notifications to return.

timeout - The maximum waiting time.

Throws:

EventClientNotFoundException - Thrown if the clientId is not found.

removeClient

public void removeClient(String clientId)
                  throws EventClientNotFoundException

Description copied from interface: EventClientDelegateMBean

Removes an added client. Calling this method will remove all listeners added with the client.

Specified by:

removeClient in interface EventClientDelegateMBean

Throws:

EventClientNotFoundException - If the clientId is not found.

lease

public long lease(String clientId,
                  long timeout)
           throws IOException,
                  EventClientNotFoundException

Description copied from interface: EventClientDelegateMBean

An EventClient calls this method to keep its clientId alive in this MBean. The client will be removed if the lease times out.

Specified by:

lease in interface EventClientDelegateMBean

Parameters:

clientId - The client's identifier.

timeout - The time in milliseconds by which the lease is to be extended. The value zero has no special meaning, so it will cause the lease to time out immediately.

Returns:

The new lifetime of the lease in milliseconds. This may be different from the requested time.

Throws:

IOException - reserved for a remote call to throw on the client side.

EventClientNotFoundException - if the clientId is not found.