public @Interface ListenerFor

The default implementation must support attaching this annotation to jakarta.faces.component.UIComponent or jakarta.faces.render.Renderer classes. In both cases, the annotation processing described herein must commence during the implementation of any variant of jakarta.faces.application.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 "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 jakarta.faces.application.Application instance.

• Determine the variant of subscribeToEvent()to call and the parameters to pass to it.

  If "target" is a UIComponent call jakarta.faces.component.UIComponent#subscribeToEvent(Class, ComponentSystemEventListener), passing the systemEventClass of the annotation as the first argument and the instance of the class to which this annotation is attached (which must implement ComponentSystemEventListener) as the second argument.

  If "target" is the jakarta.faces.application.Application instance, inspect the value of the sourceClass annotation attribute value.

  If the value is Void.class, call jakarta.faces.application.Application#subscribeToEvent(Class, SystemEventListener), passing the value of systemEventClass as the first argument and the instance of the class to which this annotation is attached (which must implement SystemEventListener) as the second argument.

  Otherwise, call jakarta.faces.application.Application#subscribeToEvent(Class, Class, SystemEventListener), passing the value of systemEventClass as the first argument, the value of sourceClass as the second argument, and the instance of the class to which this annotation is attached (which must implement SystemEventListener) as the third argument.

Example: The standard renderer for jakarta.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.