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