001/* 002 * Copyright (C) 2007 The Guava Authors 003 * 004 * Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except 005 * in compliance with the License. You may obtain a copy of the License at 006 * 007 * http://www.apache.org/licenses/LICENSE-2.0 008 * 009 * Unless required by applicable law or agreed to in writing, software distributed under the License 010 * is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express 011 * or implied. See the License for the specific language governing permissions and limitations under 012 * the License. 013 */ 014 015package com.google.common.eventbus; 016 017import com.google.common.annotations.Beta; 018import java.lang.annotation.ElementType; 019import java.lang.annotation.Retention; 020import java.lang.annotation.RetentionPolicy; 021import java.lang.annotation.Target; 022 023/** 024 * Marks a method as an event subscriber. 025 * 026 * <p>The type of event will be indicated by the method's first (and only) parameter, which cannot 027 * be primitive. If this annotation is applied to methods with zero parameters, or more than one 028 * parameter, the object containing the method will not be able to register for event delivery from 029 * the {@link EventBus}. 030 * 031 * <p>Unless also annotated with @{@link AllowConcurrentEvents}, event subscriber methods will be 032 * invoked serially by each event bus that they are registered with. 033 * 034 * @author Cliff Biffle 035 * @since 10.0 036 */ 037@Retention(RetentionPolicy.RUNTIME) 038@Target(ElementType.METHOD) 039@Beta 040public @interface Subscribe {}