org.axonframework.eventhandling

Interface EventProcessor

All Known Implementing Classes:

AbstractEventProcessor, SubscribingEventProcessor, TrackingEventProcessor

public interface EventProcessor

An Event Processor processes event messages from an event queue or event bus.

Typically, an Event Processor is in charge of publishing the events to a group of registered listeners. This allows attributes and behavior (e.g. transaction management, asynchronous processing, distribution) to be applied over a whole group at once.

Another use for Event Processors is to dispatch events to an exchange for remote processing.

Since:

1.2

Author:

Allard Buijze

Method Summary

Modifier and Type	Method and Description
String	getName() Returns the name of this event processor.
Registration	registerInterceptor(MessageHandlerInterceptor<? super EventMessage<?>> interceptor) Registers the given interceptor to this event processor.
void	shutDown() Stop processing events.
void	start() Start processing events.

Method Detail

getName

String getName()

Returns the name of this event processor. This name is used to detect distributed instances of the same event processor. Multiple instances referring to the same logical event processor (on different JVM's) must have the same name.

Returns:

the name of this event processor

registerInterceptor

Registration registerInterceptor(MessageHandlerInterceptor<? super EventMessage<?>> interceptor)

Registers the given interceptor to this event processor. The interceptor will receive each event message that is about to be published but before it has reached its event handlers. Interceptors are free to modify the event message or stop publication altogether. In addition, interceptors are able to interact with the UnitOfWork that is created to process the message.

For example, if a CorrelationDataInterceptor is registered, each command or event message triggered in response to an intercepted event will get correlation metadata from the intercepted event.

Parameters:

interceptor - The interceptor to register.

Returns:

a handle to unregister the interceptor. When unregistered the interceptor will no longer receive events from this event processor.

start

void start()

Start processing events.

shutDown

void shutDown()

Stop processing events.