ActiveMQ example source code file (XStreamMessageTransformer.java)

This example ActiveMQ source code file (XStreamMessageTransformer.java) is included in the DevDaily.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" ^TM.

Java - ActiveMQ tags/keywords

abstractxmlmessagetransformer, hierarchicalstreamdriver, hierarchicalstreamdriver, hierarchicalstreamwriter, io, jmsexception, jmsexception, object, serializable, stringwriter, stringwriter, textmessage, xppreader, xstream, xstream

The ActiveMQ XStreamMessageTransformer.java source code

/**
 * 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.util.oxm;

import java.io.Serializable;
import java.io.StringReader;
import java.io.StringWriter;

import javax.jms.JMSException;
import javax.jms.ObjectMessage;
import javax.jms.Session;
import javax.jms.TextMessage;

import com.thoughtworks.xstream.XStream;
import com.thoughtworks.xstream.io.HierarchicalStreamDriver;
import com.thoughtworks.xstream.io.HierarchicalStreamReader;
import com.thoughtworks.xstream.io.HierarchicalStreamWriter;
import com.thoughtworks.xstream.io.xml.PrettyPrintWriter;
import com.thoughtworks.xstream.io.xml.XppReader;

/**
 * Transforms object messages to text messages and vice versa using
 * {@link XStream}
 * 
 */
public class XStreamMessageTransformer extends AbstractXMLMessageTransformer {

    private XStream xStream;
    
    /**
     * Specialized driver to be used with stream readers and writers
     */
    private HierarchicalStreamDriver streamDriver;
    
    // Properties
    // -------------------------------------------------------------------------
    public XStream getXStream() {
        if (xStream == null) {
            xStream = createXStream();
        }
        return xStream;
    }

    public void setXStream(XStream xStream) {
        this.xStream = xStream;
    }

    public HierarchicalStreamDriver getStreamDriver() {
		return streamDriver;
	}

	public void setStreamDriver(HierarchicalStreamDriver streamDriver) {
		this.streamDriver = streamDriver;
	}
	
	// Implementation methods
    // -------------------------------------------------------------------------
    protected XStream createXStream() {
        return new XStream();
    }	
	
    /**
     * Marshalls the Object in the {@link ObjectMessage} to a string using XML
     * encoding
     */
    protected String marshall(Session session, ObjectMessage objectMessage) throws JMSException {
        Serializable object = objectMessage.getObject();
        StringWriter buffer = new StringWriter();
        HierarchicalStreamWriter out;
        if (streamDriver != null) {
        	out = streamDriver.createWriter(buffer);
        } else {
        	out = new PrettyPrintWriter(buffer);
        }
        getXStream().marshal(object, out);
        return buffer.toString();
    }

    /**
     * Unmarshalls the XML encoded message in the {@link TextMessage} to an
     * Object
     */
    protected Object unmarshall(Session session, TextMessage textMessage) throws JMSException {
        HierarchicalStreamReader in;
        if (streamDriver != null) {
        	in = streamDriver.createReader(new StringReader(textMessage.getText()));
        } else {
        	in = new XppReader(new StringReader(textMessage.getText()));
        }
        return getXStream().unmarshal(in);
    }

}