001/* 002 * Copyright 2002-2019 the original author or authors. 003 * 004 * Licensed under the Apache License, Version 2.0 (the "License"); 005 * you may not use this file except in compliance with the License. 006 * You may obtain a copy of the License at 007 * 008 * https://www.apache.org/licenses/LICENSE-2.0 009 * 010 * Unless required by applicable law or agreed to in writing, software 011 * distributed under the License is distributed on an "AS IS" BASIS, 012 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 013 * See the License for the specific language governing permissions and 014 * limitations under the License. 015 */ 016 017package org.springframework.messaging.handler.annotation; 018 019import java.lang.annotation.Documented; 020import java.lang.annotation.ElementType; 021import java.lang.annotation.Retention; 022import java.lang.annotation.RetentionPolicy; 023import java.lang.annotation.Target; 024 025/** 026 * Annotation that indicates a method parameter should be bound to a template variable 027 * in a destination template string. Supported on message handling methods such as 028 * {@link MessageMapping @MessageMapping}. 029 * 030 * <p>A {@code @DestinationVariable} template variable is always required. 031 * 032 * @author Brian Clozel 033 * @author Rossen Stoyanchev 034 * @since 4.0 035 * @see org.springframework.messaging.handler.annotation.MessageMapping 036 * @see org.springframework.messaging.simp.annotation.support.SimpAnnotationMethodMessageHandler 037 */ 038@Target(ElementType.PARAMETER) 039@Retention(RetentionPolicy.RUNTIME) 040@Documented 041public @interface DestinationVariable { 042 043 /** 044 * The name of the destination template variable to bind to. 045 */ 046 String value() default ""; 047 048}