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/* * Copyright 2002-2014 the original author or authors. * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * https://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ package org.springframework.messaging.converter; import org.springframework.lang.Nullable; import org.springframework.messaging.Message; import org.springframework.messaging.MessageHeaders; import org.springframework.messaging.support.MessageBuilder; import org.springframework.messaging.support.MessageHeaderAccessor; import org.springframework.util.ClassUtils; /** * A simple converter that simply unwraps the message payload as long as it matches the * expected target class. Or reversely, simply wraps the payload in a message. * * <p>Note that this converter ignores any content type information that may be present in * message headers and should not be used if payload conversion is actually required. * * @author Rossen Stoyanchev * @since 4.0 */ public class SimpleMessageConverter implements MessageConverter { @Override @Nullable public Object fromMessage(Message<?> message, Class<?> targetClass) { Object payload = message.getPayload(); return (ClassUtils.isAssignableValue(targetClass, payload) ? payload : null); } @Override public Message<?> toMessage(Object payload, @Nullable MessageHeaders headers) { if (headers != null) { MessageHeaderAccessor accessor = MessageHeaderAccessor.getAccessor(headers, MessageHeaderAccessor.class); if (accessor != null && accessor.isMutable()) { return MessageBuilder.createMessage(payload, accessor.getMessageHeaders()); } } return MessageBuilder.withPayload(payload).copyHeaders(headers).build(); } }