org.axonframework.eventhandling

Interface EventListener

All Known Subinterfaces:

EventListenerProxy, Saga<T>

All Known Implementing Classes:

AnnotatedSaga, AnnotationEventListenerAdapter, EventValidator

Functional Interface:

This is a functional interface and can therefore be used as the assignment target for a lambda expression or method reference.

@FunctionalInterface
public interface EventListener

Interface to be implemented by classes that can handle events.

Since:

0.1

Author:

Allard Buijze

See Also:

EventBus, DomainEventMessage, EventHandler

Method Summary

Modifier and Type	Method and Description
default boolean	canHandle(EventMessage<?> event) Indicates whether this listener can handle the given event message
void	handle(EventMessage<?> event) Process the given event.
default void	prepareReset() Performs any activities that are required to reset the state managed by handlers assigned to this invoker.
default boolean	supportsReset() Indicates whether the handlers managed by this invoker support a reset.

Method Detail

handle

void handle(EventMessage<?> event)
     throws Exception

Process the given event. The implementation may decide to process or skip the given event. It is highly unrecommended to throw any exception during the event handling process.

Parameters:

event - the event to handle

Throws:

Exception - when an exception is raised during event handling

canHandle

default boolean canHandle(EventMessage<?> event)

Indicates whether this listener can handle the given event message

Parameters:

event - The event message to verify

Returns:

true if this listener can handle the event, otherwise false

prepareReset

default void prepareReset()

Performs any activities that are required to reset the state managed by handlers assigned to this invoker.

supportsReset

default boolean supportsReset()

Indicates whether the handlers managed by this invoker support a reset.

Returns:

true if a reset is supported, otherwise false