Annotation Type ListenerFor
Classes tagged with this annotation are
installed as listeners using the method Application.subscribeToEvent(java.lang.Class<? extends javax.faces.event.SystemEvent>, java.lang.Class<?>, javax.faces.event.SystemEventListener)
or UIComponent.subscribeToEvent(java.lang.Class<? extends javax.faces.event.SystemEvent>, javax.faces.event.ComponentSystemEventListener)
(depending on the
circumstances, described below).
The default implementation must support attaching this annotation
to UIComponent
or Renderer
classes. In both cases, the annotation
processing described herein must commence during the implementation
of any variant of Application
.createComponent()
and must complete before the UIComponent
instance is
returned from createComponent()
. The annotation
processing must proceed according to an algorithm semantically
equivalent to the following.
If this annotation is not present on the class in question, no action must be taken.
-
Determine the variant of
subscribeToEvent()
to call and the parameters to pass to it.If "target" is a
UIComponent
callUIComponent.subscribeToEvent(Class, ComponentSystemEventListener)
, passing thesystemEventClass()
of the annotation as the first argument and the instance of the class to which this annotation is attached (which must implementComponentSystemEventListener
) as the second argument.If "target" is the
Application
instance, inspect the value of thesourceClass()
annotation attribute value.If the value is
Void.class
, callApplication.subscribeToEvent(Class, SystemEventListener)
, passing the value ofsystemEventClass()
as the first argument and the instance of the class to which this annotation is attached (which must implementSystemEventListener) as the second argument.
Otherwise, call
Application.subscribeToEvent(Class, Class, SystemEventListener)
, passing the value ofsystemEventClass()
as the first argument, the value ofsourceClass()
as the second argument, and the instance of the class to which this annotation is attached (which must implementSystemEventListener) as the third argument.
Determine the "target" on which to call
subscribeToEvent
.
If the class to which this annotation is attached
implements ComponentSystemEventListener
and is a
UIComponent
instance, "target" is the
UIComponent
instance.
If the class to which this annotation is attached
implements ComponentSystemEventListener
and is a
Renderer
instance, "target" is the
UIComponent
instance that is to be rendered by
this Renderer
instance.
If the class to which this annotation is attached
implements ComponentSystemEventListener
and is neither
an instance of Renderer
nor
UIComponent
, the action taken is
unspecified. This case must not trigger any kind of error.
If the class to which this annotation is attached
implements SystemEventListener
and does not
implement ComponentSystemEventListener
, "target"
is the Application
instance.
Example: The standard renderer for
javax.faces.resource.Stylesheet
must have the following
annotation declaration:
@ListenerFor(systemEventClass=PostAddToViewEvent.class)
This will cause the renderer to be added as a listener for the
PostAddToViewEvent
to all components that list it as their
renderer.
- Since:
- 2.0
-
Required Element Summary
Required ElementsModifier and TypeRequired ElementDescriptionClass
<? extends SystemEvent> The kind of system event for which this class will be installed as a listener. -
Optional Element Summary
Optional ElementsModifier and TypeOptional ElementDescriptionThe kind of object that emits events of the type given by the value of thesystemEventClass()
attribute.
-
Element Details
-
systemEventClass
Class<? extends SystemEvent> systemEventClassThe kind of system event for which this class will be installed as a listener. The implementation only supports exact matches on the
Class
and must not honor subclass relationships. It is valid to have EL Expressions in the value of this attribute, as long as the expression resolves to an instance of the expected type. -
sourceClass
Class sourceClassThe kind of object that emits events of the type given by the value of the
systemEventClass()
attribute. It is valid to have EL Expressions in the value of this attribute, as long as the expression resolves to an instance of the expected type.- Default:
java.lang.Void.class
-