/**
* 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.xstream;
import java.io.Serializable;
import java.io.StringReader;
import java.io.StringWriter;
import javax.jms.JMSException;
import javax.jms.Message;
import javax.jms.MessageConsumer;
import javax.jms.MessageProducer;
import javax.jms.ObjectMessage;
import javax.jms.Session;
import javax.jms.TextMessage;
import org.apache.activemq.MessageTransformerSupport;
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}
*
* @deprecated as of 5.3.0 release replaced by {@link org.apache.activemq.util.oxm.XStreamMessageTransformer}
*
* @version $Revision: 814586 $
*/
@Deprecated
public class XStreamMessageTransformer extends MessageTransformerSupport {
protected MessageTransform transformType;
private XStream xStream;
/**
* Specialized driver to be used with stream readers and writers
*/
private HierarchicalStreamDriver streamDriver;
/**
* Defines the type of transformation. If XML (default), - producer
* transformation transforms from Object to XML. - consumer transformation
* transforms from XML to Object. If OBJECT, - producer transformation
* transforms from XML to Object. - consumer transformation transforms from
* Object to XML. If ADAPTIVE, - producer transformation transforms from
* Object to XML, or XML to Object depending on the type of the original
* message - consumer transformation transforms from XML to Object, or
* Object to XML depending on the type of the original message
*/
public enum MessageTransform {
XML, OBJECT, ADAPTIVE
};
public XStreamMessageTransformer() {
this(MessageTransform.XML);
}
public XStreamMessageTransformer(MessageTransform transformType) {
this.transformType = transformType;
}
public Message consumerTransform(Session session, MessageConsumer consumer, Message message) throws JMSException {
switch (transformType) {
case XML:
return (message instanceof TextMessage) ? textToObject(session, (TextMessage)message) : message;
case OBJECT:
return (message instanceof ObjectMessage) ? objectToText(session, (ObjectMessage)message) : message;
case ADAPTIVE:
return (message instanceof TextMessage) ? textToObject(session, (TextMessage)message) : (message instanceof ObjectMessage) ? objectToText(session, (ObjectMessage)message) : message;
default:
}
return message;
}
public Message producerTransform(Session session, MessageProducer producer, Message message) throws JMSException {
switch (transformType) {
case XML:
return (message instanceof ObjectMessage) ? objectToText(session, (ObjectMessage)message) : message;
case OBJECT:
return (message instanceof TextMessage) ? textToObject(session, (TextMessage)message) : message;
case ADAPTIVE:
return (message instanceof TextMessage) ? textToObject(session, (TextMessage)message) : (message instanceof ObjectMessage) ? objectToText(session, (ObjectMessage)message) : message;
default:
}
return message;
}
// 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();
}
public MessageTransform getTransformType() {
return transformType;
}
public void setTransformType(MessageTransform transformType) {
this.transformType = transformType;
}
/**
* Transforms an incoming XML encoded {@link TextMessage} to an
* {@link ObjectMessage}
*
* @param session - JMS session currently being used
* @param textMessage - text message to transform to object message
* @return ObjectMessage
* @throws JMSException
*/
protected ObjectMessage textToObject(Session session, TextMessage textMessage) throws JMSException {
Object object = unmarshall(session, textMessage);
if (object instanceof Serializable) {
ObjectMessage answer = session.createObjectMessage((Serializable)object);
copyProperties(textMessage, answer);
return answer;
} else {
throw new JMSException("Object is not serializable: " + object);
}
}
/**
* Transforms an incoming {@link ObjectMessage} to an XML encoded
* {@link TextMessage}
*
* @param session - JMS session currently being used
* @param objectMessage - object message to transform to text message
* @return XML encoded TextMessage
* @throws JMSException
*/
protected TextMessage objectToText(Session session, ObjectMessage objectMessage) throws JMSException {
TextMessage answer = session.createTextMessage(marshall(session, objectMessage));
copyProperties(objectMessage, answer);
return answer;
}
/**
* 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);
}
}