001/** 002 * Licensed to the Apache Software Foundation (ASF) under one or more 003 * contributor license agreements. See the NOTICE file distributed with 004 * this work for additional information regarding copyright ownership. 005 * The ASF licenses this file to You under the Apache License, Version 2.0 006 * (the "License"); you may not use this file except in compliance with 007 * the License. You may obtain a copy of the License at 008 * 009 * http://www.apache.org/licenses/LICENSE-2.0 010 * 011 * Unless required by applicable law or agreed to in writing, software 012 * distributed under the License is distributed on an "AS IS" BASIS, 013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 014 * See the License for the specific language governing permissions and 015 * limitations under the License. 016 */ 017package org.apache.camel.processor.aggregate; 018 019import java.util.List; 020 021import org.apache.camel.Exchange; 022import org.apache.camel.Message; 023import org.apache.camel.impl.DefaultExchange; 024 025/** 026 * Aggregate all {@link Message} into a single combined Exchange holding all the 027 * aggregated messages in a {@link List} of {@link Message} as the message body. 028 * 029 * This aggregation strategy can used in combination with {@link org.apache.camel.processor.Splitter} to batch messages 030 * 031 * @version 032 */ 033public class GroupedMessageAggregationStrategy extends AbstractListAggregationStrategy<Message> { 034 035 @Override 036 public Exchange aggregate(Exchange oldExchange, Exchange newExchange) { 037 if (oldExchange == null) { 038 // for the first time we must create a new empty exchange as the 039 // holder, as the outgoing exchange 040 // must not be one of the grouped exchanges, as that causes a 041 // endless circular reference 042 oldExchange = new DefaultExchange(newExchange); 043 } 044 return super.aggregate(oldExchange, newExchange); 045 } 046 047 @Override 048 public Message getValue(Exchange exchange) { 049 return exchange.getIn(); 050 } 051}