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 17 package com.google.common.eventbus; 18 19 import com.google.common.annotations.Beta; 20 21 import java.lang.annotation.ElementType; 22 import java.lang.annotation.Retention; 23 import java.lang.annotation.RetentionPolicy; 24 import java.lang.annotation.Target; 25 26 /** 27 * Marks a method as an event subscriber. 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 subscriber 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 44 public @interface Subscribe { 45 } 46