001/* 002 * Copyright 2002-2014 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.converter; 018 019import org.springframework.messaging.Message; 020import org.springframework.messaging.MessageHeaders; 021import org.springframework.messaging.support.MessageBuilder; 022import org.springframework.messaging.support.MessageHeaderAccessor; 023import org.springframework.util.ClassUtils; 024 025/** 026 * A simple converter that simply unwraps the message payload as long as it matches the 027 * expected target class. Or reversely, simply wraps the payload in a message. 028 * 029 * <p>Note that this converter ignores any content type information that may be present in 030 * message headers and should not be used if payload conversion is actually required. 031 * 032 * @author Rossen Stoyanchev 033 * @since 4.0 034 */ 035public class SimpleMessageConverter implements MessageConverter { 036 037 @Override 038 public Object fromMessage(Message<?> message, Class<?> targetClass) { 039 Object payload = message.getPayload(); 040 if (targetClass == null) { 041 return payload; 042 } 043 return (ClassUtils.isAssignableValue(targetClass, payload) ? payload : null); 044 } 045 046 @Override 047 public Message<?> toMessage(Object payload, MessageHeaders headers) { 048 if (payload == null) { 049 return null; 050 } 051 if (headers != null) { 052 MessageHeaderAccessor accessor = MessageHeaderAccessor.getAccessor(headers, MessageHeaderAccessor.class); 053 if (accessor != null && accessor.isMutable()) { 054 return MessageBuilder.createMessage(payload, accessor.getMessageHeaders()); 055 } 056 } 057 return MessageBuilder.withPayload(payload).copyHeaders(headers).build(); 058 } 059 060}