Class NamingEvent
- All Implemented Interfaces:
Serializable
The NamingEvent
's state consists of
- The event source: the
EventContext
which fired this event. - The event type.
- The new binding: information about the object after the change.
- The old binding: information about the object before the change.
- Change information: information about the change that triggered this event; usually service provider-specific or server-specific information.
Note that the event source is always the same EventContext
instance that the listener has registered with.
Furthermore, the names of the bindings in
the NamingEvent
are always relative to that instance.
For example, suppose a listener makes the following registration:
When an object named "x/y" is subsequently deleted, the correspondingNamespaceChangeListener listener = ...; src.addNamingListener("x", SUBTREE_SCOPE, listener);
NamingEvent
(evt
) must contain:
Care must be taken when multiple threads are accessing the sameevt.getEventContext() == src evt.getOldBinding().getName().equals("x/y")
EventContext
concurrently.
See the
package description
for more information on threading issues.- Since:
- 1.3
- See Also:
-
Field Summary
Modifier and TypeFieldDescriptionprotected Object
Contains information about the change that generated this event.protected Binding
Contains information about the object after the change.static final int
Naming event type for indicating that a new object has been added.static final int
Naming event type for indicating that an object has been changed.static final int
Naming event type for indicating that an object has been removed.static final int
Naming event type for indicating that an object has been renamed.protected Binding
Contains information about the object before the change.protected int
Contains the type of this event.Fields inherited from class java.util.EventObject
source
-
Constructor Summary
ConstructorDescriptionNamingEvent
(EventContext source, int type, Binding newBd, Binding oldBd, Object changeInfo) Constructs an instance ofNamingEvent
. -
Method Summary
Modifier and TypeMethodDescriptionvoid
dispatch
(NamingListener listener) Invokes the appropriate listener method on this event.Retrieves the change information for this event.Retrieves the event source that fired this event.Retrieves the binding of the object after the change.Retrieves the binding of the object before the change.int
getType()
Returns the type of this event.Methods inherited from class java.util.EventObject
getSource, toString
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Field Details
-
OBJECT_ADDED
public static final int OBJECT_ADDEDNaming event type for indicating that a new object has been added. The value of this constant is0
.- See Also:
-
OBJECT_REMOVED
public static final int OBJECT_REMOVEDNaming event type for indicating that an object has been removed. The value of this constant is1
.- See Also:
-
OBJECT_RENAMED
public static final int OBJECT_RENAMEDNaming event type for indicating that an object has been renamed. Note that some services might fire multiple events for a single logical rename operation. For example, the rename operation might be implemented by adding a binding with the new name and removing the old binding.The old/new binding in
NamingEvent
may be null if the old name or new name is outside of the scope for which the listener has registered.When an interior node in the namespace tree has been renamed, the topmost node which is part of the listener's scope should used to generate a rename event. The extent to which this can be supported is provider-specific. For example, a service might generate rename notifications for all descendants of the changed interior node and the corresponding provider might not be able to prevent those notifications from being propagated to the listeners.
The value of this constant is
2
.- See Also:
-
OBJECT_CHANGED
public static final int OBJECT_CHANGEDNaming event type for indicating that an object has been changed. The changes might include the object's attributes, or the object itself. Note that some services might fire multiple events for a single modification. For example, the modification might be implemented by first removing the old binding and adding a new binding containing the same name but a different object.The value of this constant is
3
.- See Also:
-
changeInfo
Contains information about the change that generated this event. -
type
protected int typeContains the type of this event.- See Also:
-
oldBinding
Contains information about the object before the change. -
newBinding
Contains information about the object after the change.
-
-
Constructor Details
-
NamingEvent
Constructs an instance ofNamingEvent
.The names in
newBd
andoldBd
are to be resolved relative to the event sourcesource
. For anOBJECT_ADDED
event type,newBd
must not be null. For anOBJECT_REMOVED
event type,oldBd
must not be null. For anOBJECT_CHANGED
event type,newBd
andoldBd
must not be null. For anOBJECT_RENAMED
event type, one ofnewBd
oroldBd
may be null if the new or old binding is outside of the scope for which the listener has registered.- Parameters:
source
- The non-null context that fired this event.type
- The type of the event.newBd
- A possibly null binding before the change. See method description.oldBd
- A possibly null binding after the change. See method description.changeInfo
- A possibly null object containing information about the change.- See Also:
-
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Method Details
-
getType
public int getType()Returns the type of this event.- Returns:
- The type of this event.
- See Also:
-
getEventContext
Retrieves the event source that fired this event. This returns the same object asEventObject.getSource()
.If the result of this method is used to access the event source, for example, to look up the object or get its attributes, then it needs to be locked because implementations of
Context
are not guaranteed to be thread-safe (andEventContext
is a subinterface ofContext
). See the package description for more information on threading issues.- Returns:
- The non-null context that fired this event.
-
getOldBinding
Retrieves the binding of the object before the change.The binding must be nonnull if the object existed before the change relative to the source context (
getEventContext()
). That is, it must be nonnull forOBJECT_REMOVED
andOBJECT_CHANGED
. ForOBJECT_RENAMED
, it is null if the object before the rename is outside of the scope for which the listener has registered interest; it is nonnull if the object is inside the scope before the rename.The name in the binding is to be resolved relative to the event source
getEventContext()
. The object returned byBinding.getObject()
may be null if such information is unavailable.- Returns:
- The possibly null binding of the object before the change.
-
getNewBinding
Retrieves the binding of the object after the change.The binding must be nonnull if the object existed after the change relative to the source context (
getEventContext()
). That is, it must be nonnull forOBJECT_ADDED
andOBJECT_CHANGED
. ForOBJECT_RENAMED
, it is null if the object after the rename is outside the scope for which the listener registered interest; it is nonnull if the object is inside the scope after the rename.The name in the binding is to be resolved relative to the event source
getEventContext()
. The object returned byBinding.getObject()
may be null if such information is unavailable.- Returns:
- The possibly null binding of the object after the change.
-
getChangeInfo
Retrieves the change information for this event. The value of the change information is service-specific. For example, it could be an ID that identifies the change in a change log on the server.- Returns:
- The possibly null change information of this event.
-
dispatch
Invokes the appropriate listener method on this event. The default implementation of this method handles the following event types:OBJECT_ADDED, OBJECT_REMOVED, OBJECT_RENAMED, OBJECT_CHANGED
.The listener method is executed in the same thread as this method. See the package description for more information on threading issues.
- Parameters:
listener
- The nonnull listener.
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