io.cloudstate.javasupport.eventsourced.EventHandler Maven / Gradle / Ivy
package io.cloudstate.javasupport.eventsourced;
import io.cloudstate.javasupport.impl.CloudStateAnnotation;
import java.lang.annotation.ElementType;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.lang.annotation.Target;
/**
* Marks a method as an event handler.
*
* This method will be invoked whenever an event matching this event handlers event class is
* either replayed on entity recovery, by a command handler.
*
*
The method may take the event object as a parameter.
*
*
Methods annotated with this may take an {@link EventContext}.
*/
@CloudStateAnnotation
@Target(ElementType.METHOD)
@Retention(RetentionPolicy.RUNTIME)
public @interface EventHandler {
/**
* The event class. Generally, this will be determined by looking at the parameter of the event
* handler method, however if the event doesn't need to be passed to the method (for example,
* perhaps it contains no data), then this can be used to indicate which event this handler
* handles.
*/
Class eventClass() default Object.class;
}