org.jmolecules.event.annotation.DomainEventHandler Maven / Gradle / Ivy
/*
* Copyright 2020-2021 the original author or authors.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* https://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.jmolecules.event.annotation;
import java.lang.annotation.Documented;
import java.lang.annotation.ElementType;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.lang.annotation.Target;
/**
* Identifies a domain event handler, i.e. logic to process a {@link DomainEvent}.
*
* @author Christian Stettler
* @author Henning Schwentner
* @author Stephan Pirnbaum
* @author Martin Schimak
* @author Oliver Drotbohm
* @since 1.1
*/
@Documented
@Retention(RetentionPolicy.RUNTIME)
@Target({ ElementType.METHOD, ElementType.ANNOTATION_TYPE })
public @interface DomainEventHandler {
/**
* Optional identification of the namespace of the domain event handled by this handler. This information may be used
* for easier linkage between event and handler by external tools and refers to {@link DomainEvent#namespace()}. When
* leaving the default value, it is assumed that the method signature makes clear what event is consumed. If the
* handler takes care of all events of a specific namespace, the value of this field needs to be set to the respective
* namespace and the {@link DomainEventHandler#name()} needs to be set accordingly. If the handler doesn't care about
* the namespace, the value may be set to the '*' (asterisk) placeholder.
*/
String namespace() default "";
/**
* Optional identification of the name of the domain event handled by this handler. This information may be used for
* easier linkage between event and handler by external tools and refers to {@link DomainEvent#name()}. When leaving
* the default value, it is assumed that the method signature makes clear what event is consumed. If the handler takes
* care of all events of a specific namespace, the value of this field needs to be set to the '*' asterisk
* placeholder.
*/
String name() default "";
}