trunk/activemq-core/src/main/java/org/apache/activemq/broker/util/TraceBrokerPathPlugin.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.activemq.broker.util;

import java.io.IOException;
import java.util.Map;

import org.apache.activemq.broker.BrokerPluginSupport;
import org.apache.activemq.command.MessageDispatch;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

/**
 * The TraceBrokerPathPlugin can be used in a network of Brokers. Each Broker 
 * that has the plugin configured, will add it's brokerName to the content 
 * of a JMS Property. If all Brokers have this property enabled, the path the 
 * message actually took through the network can be seen in the defined property.
 * 
 * @org.apache.xbean.XBean element="traceBrokerPathPlugin"
 * 
 * 
 */

public class TraceBrokerPathPlugin extends BrokerPluginSupport {

	private String stampProperty = "BrokerPath";
    private static final Logger LOG = LoggerFactory.getLogger(TraceBrokerPathPlugin.class);
	
	public String getStampProperty() {
		return stampProperty;
	}

	public void setStampProperty(String stampProperty) {
		this.stampProperty = stampProperty;
	}

	public void preProcessDispatch(MessageDispatch messageDispatch) {
		try {
    		String brokerStamp = (String)messageDispatch.getMessage().getProperty(getStampProperty());
    		if (brokerStamp == null) {
    			brokerStamp = getBrokerName();
    		} else {
    			brokerStamp += "," + getBrokerName();
    		}
    		messageDispatch.getMessage().setProperty(getStampProperty(), brokerStamp);
		} catch (IOException ioe) {
			LOG.warn("Setting broker property failed " + ioe, ioe);
		}
		super.preProcessDispatch(messageDispatch);
	}
}