/* * Licensed to the Apache Software Foundation (ASF) under one or more * contributor license agreements. See the NOTICE file distributed with * this work for additional information regarding copyright ownership. * The ASF licenses this file to You 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 * * http://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. * * $Header:$ */ package org.apache.beehive.controls.api.events; import java.lang.annotation.ElementType; import java.lang.annotation.Retention; import java.lang.annotation.RetentionPolicy; import java.lang.annotation.Target; /** * The EventSet annotation type is used to mark an interface that defines a group of events * associated with a Java Control. By convention, event interfaces are defined as inner * classes on the Java Control public interface. Each method defined within a * event interface indicates an event that can be delivered by the control. *
* Here is a simple example:
*
* This will declare an event interface named
* public interface MyControl extends org.apache.beehive.controls.api.Control
* {
*
MyEvents
that declares a single
* event: anEvent
*
* The declaration of an EventSet for a control also means that the associated Control
* JavaBean will have listener registration/deregistration APIs. The name of these
* APIs will be add/remove
* The above example would result in the following APIs on MyControlBean
*
*
*/
@Retention(RetentionPolicy.RUNTIME)
@Target({ElementType.TYPE})
public @interface EventSet
{
/**
* Defines whether the events defined by the interface are unicast events. A unicast
* event set may have only a single listener registered to receive events for any
* given bean instance. Any attempt to register additional listeners will result in
* a
* public class MyControlBean implements MyControl
* {
* ...
* public void addMyEventsListener(MyEvents listener) { ... }
* public void removeMyEventsListener(MyEvents listener) { ... }
*
java.util.TooManyListenersException
being thrown by the event
* listener registration method.
*
* If an event set provides multicast support (the default), then it may only declare
* event methods that have a void
return type. Unicast event sets may
* support event return values, that will be provided by the (single) registered
* listener.
*/
public boolean unicast() default false;
}