com.edorasware.gear.core.event.internal

Interface EventBus

All Known Implementing Classes:

SynchronousMemoryBasedEventBus

public interface EventBus

Represents a generic event bus mechanisms with support for multiple listeners per event type. Events posted via dispatchEvent(Event) are dispatched to all interested listeners registered via register(EventHandler, Class), based on the type of the Event. <p> Aspects like event persistence, reliability, and synchronous/asynchronous delivery of events is subject to the implementation.

Method Summary

Modifier and Type	Method and Description
void	dispatchEvent(Event event) Dispatches the event to all event handlers registered for the corresponding event type or event supertype.
<E extends Event> void	register(EventHandler<? super E> eventHandler, Class<E> eventType) Registers the event handler for being notified on events of the specified type and all subtypes.
<E extends Event> void	unregister(EventHandler<? super E> eventHandler, Class<E> eventType) Unregisters the event handler from being notified on events of the specified type and all subtypes.

Method Detail

register

<E extends Event> void register(EventHandler<? super E> eventHandler,
                                Class<E> eventType)

Registers the event handler for being notified on events of the specified type and all subtypes. Registering the same event handler for different event types is supported, as long as the event type is compatible with the event type expected by the event handler. Registering an already registered event handler for the same event type has no effect. <p> Explicitly registering an event handler for an event type and for a subtype of that event type is seen as two separate, unrelated registrations, and thus, events of the subtype will be dispatched to the event handler twice.

Parameters:

eventHandler - the event handler to be registered

eventType - the type of the event to register the event handler with

unregister

<E extends Event> void unregister(EventHandler<? super E> eventHandler,
                                  Class<E> eventType)

Unregisters the event handler from being notified on events of the specified type and all subtypes. Other registrations of the same event handler for different event types are not affected. If the event handler has not been registered for the corresponding event type, this operation has no effect. <p> Unregistering the event handler for a specific event type does not automatically unregister the same event handler from all subtypes of that event type, in case the event handler has explicitly been registered for both the event type and the event subtype.

Parameters:

eventHandler - the event handler to be unregistered

eventType - the type of the event to unregister the event handler from

dispatchEvent

void dispatchEvent(Event event)

Dispatches the event to all event handlers registered for the corresponding event type or event supertype. If no event handlers are registered for this event type, this operation has no effect.

Parameters:

event - the event to be dispatched