1/*
2 * Copyright (C) 2007 The Guava Authors
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 * http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17package com.google.common.eventbus;
18
19import com.google.common.annotations.Beta;
20import java.lang.annotation.ElementType;
21import java.lang.annotation.Retention;
22import java.lang.annotation.RetentionPolicy;
23import java.lang.annotation.Target;
24
25/**
26 * Marks a method as an event handler, as used by
27 * {@link AnnotatedHandlerFinder} and {@link EventBus}.
28 *
29 * <p>The type of event will be indicated by the method's first (and only)
30 * parameter.  If this annotation is applied to methods with zero parameters,
31 * or more than one parameter, the object containing the method will not be able
32 * to register for event delivery from the {@link EventBus}.
33 *
34 * <p>Unless also annotated with @{@link AllowConcurrentEvents}, event handler
35 * methods will be invoked serially by each event bus that they are registered
36 * with.
37 *
38 * @author Cliff Biffle
39 * @since 10.0
40 */
41@Retention(RetentionPolicy.RUNTIME)
42@Target(ElementType.METHOD)
43@Beta
44public @interface Subscribe {
45}
46