examples/camel-example-loan-broker/src/main/java/org/apache/camel/loanbroker/queue/version/BankResponseAggregationStrategy.java

/**
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You 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.apache.camel.loanbroker.queue.version;

import org.apache.camel.Exchange;
import org.apache.camel.Message;
import org.apache.camel.processor.aggregate.AggregationStrategy;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;

//START SNIPPET: aggregation
public class BankResponseAggregationStrategy implements AggregationStrategy {    
    private static final transient Log LOG = LogFactory.getLog(BankResponseAggregationStrategy.class);
    private boolean aggregatingOutMessage;
    
    public BankResponseAggregationStrategy setAggregatingOutMessage(boolean flag) {
        aggregatingOutMessage = flag;
        return this;
    }
    
    // Here we put the bank response together
    public Exchange aggregate(Exchange oldExchange, Exchange newExchange) {
        LOG.debug("Get the exchange to aggregate, older: " + oldExchange + " newer:" + newExchange);
        Message oldMessage = null;
        Message newMessage = null;
        if (aggregatingOutMessage) {
            oldMessage = oldExchange.getOut(false);
            newMessage = newExchange.getOut(false);
        } else {
            oldMessage = oldExchange.getIn();
            newMessage = newExchange.getIn();
        }
        Double oldRate = oldMessage.getHeader(Constants.PROPERTY_RATE, Double.class);
        Double newRate = newMessage.getHeader(Constants.PROPERTY_RATE, Double.class);
        Exchange result = null;

        if (newRate >= oldRate) {
            result = oldExchange;
        } else {
            result = newExchange;
        }
        LOG.debug("Get the lower rate exchange " + result);

        return result;

    }

}
// END SNIPPET: aggregation