/* * 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 * * http://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.support; import org.springframework.messaging.Message; import org.springframework.messaging.MessageChannel; /** * A simpler interceptor that calls {@link MessageHeaderAccessor#setImmutable()} * on the headers of messages passed through the preSend method. * * <p>When configured as the last interceptor in a chain, it allows the component * sending the message to leave headers mutable for interceptors to modify prior * to the message actually being sent and exposed to concurrent access. * * @author Rossen Stoyanchev * @since 4.1.2 */ public class ImmutableMessageChannelInterceptor extends ChannelInterceptorAdapter { @Override public Message<?> preSend(Message<?> message, MessageChannel channel) { MessageHeaderAccessor accessor = MessageHeaderAccessor.getAccessor(message, MessageHeaderAccessor.class); if (accessor != null && accessor.isMutable()) { accessor.setImmutable(); } return message; } }