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 */
017 package org.apache.camel.processor.aggregate;
018
019 import org.apache.camel.Exchange;
020
021 /**
022 * An {@link AggregationStrategy} which just uses the latest exchange which is useful
023 * for status messages where old status messages have no real value. Another example is things
024 * like market data prices, where old stock prices are not that relevant, only the current price is.
025 *
026 * @version $Revision: 752465 $
027 */
028 public class UseLatestAggregationStrategy implements AggregationStrategy {
029
030 public Exchange aggregate(Exchange oldExchange, Exchange newExchange) {
031 newExchange.setException(checkException(oldExchange, newExchange));
032 return newExchange;
033 }
034
035 protected Exception checkException(Exchange oldExchange, Exchange newExchange) {
036 return newExchange.getException() != null
037 ? newExchange.getException()
038 : oldExchange.getException();
039 }
040 }