Distributed Transactions

I need to perform a distributed transaction in My Servlet.
My distributed transaction involves Updating to the DB and also publishing a message to a queue.
The queue is not present in my app server, where my Servlet is running.
It is there on a remote machine.

I'm using below code to achieve the same.
But I'm not getting the transactional behaviour working... That means
If I publish a message to queue and then if DB Operation fails, the transaction should roll back and the queue should not be having any contents.
But my queue is still showing me the contents...

Any glitches in my code???

public class RemoteServlet extends javax.servlet.http.HttpServlet implements
		javax.servlet.Servlet {
	private QueueConnectionFactory queueConnectionFactory;
	private Queue queue;	
	private QueueConnection queueConnection = null;
	private QueueSession queueSession = null;
	private QueueSender queueSender = null;
	private TextMessage message = null;

@Resource
	UserTransaction utx;
	
	protected void doBatch(HttpServletRequest request,
			HttpServletResponse response) throws Exception {
		try {
			initQueue();

utx.begin();
			publishMessage(false);
			updateDB();//Some DB Operation which will fail to test the rollback		
			utx.commit();
		} catch (Exception e) {
			utx.rollback();
			e.printStackTrace();
		} finally {
			closeJMS();
		}
		
		printQueue();
	}
	
	private void closeJMS() {
		try {
			queueSession.close();
			queueConnection.close();
		} catch (JMSException jmse) {
			jmse.printStackTrace();
		}
	}
	
	private void publishMessage() throws Exception {
 for ( int i = 1; i < 5; i++) {
 	message = queueSession.createTextMessage();
 		message.setText("Current Time is (" + (new Date().getTime() + i) + "):: " + new Date());
 		System.out.println(" " + "Sending message :: " + message.getText());
 		queueSender.send(message);
 }
	}
		
	public void initQueue() throws Exception {
		Context ctx = getInitialContext();
		Object obj = null;
		try {
			queueConnectionFactory = (QueueConnectionFactory) ctx.lookup("jmsfactory/default/MyQueueConnectionFactoryXA");
			queue = (Queue) ctx.lookup("jmsqueues/default/MyQueue");
			queueConnection = queueConnectionFactory.createQueueConnection();
			queueSession = queueConnection.createQueueSession(true, Session.AUTO_ACKNOWLEDGE);
			queueSender = queueSession.createSender(queue);
			queueConnection.start();
		} catch (Exception e) {
			e.printStackTrace();
		}
	}

public void printQueue(String desc) {
		try {
			QueueBrowser browser = queueSession.createBrowser(queue);
			Enumeration<TextMessage> en = browser.getEnumeration();
 
			while (en.hasMoreElements()) {
			 TextMessage queueBrMessage = en.nextElement();
			 System.out .println( " " + queueBrMessage.getText());
			}
		} catch (JMSException e) {
			e.printStackTrace();
		}
	}
	
	public Context getInitialContext() throws Exception {
		Properties properties = new Properties();
		properties.put(Context.INITIAL_CONTEXT_FACTORY, "com.sap.engine.services.jndi.InitialContextFactoryImpl");
		properties.put(Context.PROVIDER_URL, "10.134.162.75:50004"); // IP Address of the Host where the Queue is setup
		properties.put(Context.SECURITY_PRINCIPAL, "Administrator");
		properties.put(Context.SECURITY_CREDENTIALS, "password");
		properties.put("force_remote", "true");
		InitialContext context = new InitialContext(properties);
		return context;
	}
	
	public RemoteServlet() {
		super();
	}

protected void doGet(HttpServletRequest request,
			HttpServletResponse response) throws ServletException, IOException {
		try {
			doBatch(request, response);
		} catch (Exception e) {
			e.printStackTrace();
		}
	}
}

To achive this behaviour you can go for the Transaction Attribute Mantadatory on to the caller .

(Mantadatory is for updating the Database contents ) and the queue method consiting of another Method .)

Can you please give some more details on how to achieve what you said?

I need to do this in my Servlet. I'm not using any EJB Components/Spring

I have the same problem .Has any body found any solution to it

1. use the XA versions of the implementations.
2. make sure you are using an XA driver.
3. Do not specify a transacted session..JTA user transactions are ignored by transacted sessions and you cannot include other resources in transactions when you use a transacted session for jms. Specify false in the first arg to connection.createSession() method.

The original code will not even compile. There is no publishMessage() method that accepts a bolean var.

For example

ram.

I tried using false to not to use transacted session. But am still getting the same error

My code is like below. I am clueless what is missing.
I am using SAP NetWeaver Application Server

In my below code, Even after I rollback my JTA UserTransaction, the JMS operations are not rolling back.

public class JMSSender extends javax.servlet.http.HttpServlet implements javax.servlet.Servlet {
 static final long serialVersionUID = 1L;
 
 	PrintWriter out;
 	
 	private XAQueueConnectionFactory queueConnectionFactory;
	private Queue queue;	
	private QueueSession queueSession = null;
	private QueueSender queueSender = null;
	private TextMessage message = null;
	private XAQueueConnection queueConnection = null;
	
	@Resource
	UserTransaction utx;
	
	protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
		out = response.getWriter();
 
		try {
			utx.begin();
			
			initQueue();
			printQueue("Q Before");
			publishMessage(false);
 
			utx.rollback();
			//utx.commit();
		} catch (Exception e) {
			e.printStackTrace(out);
			try {
				utx.rollback();
			} catch (Exception e1) {
				e1.printStackTrace();
			} 
		} finally {
			printQueue("Finally");
			closeJMS();
		}
	}
	
	public void publishMessage(boolean rollBackFlag) throws Exception {
		int rand = new Random(100).nextInt();
		for ( int i = 1; i < 5; i++) {
 	message = queueSession.createTextMessage();
 		message.setText("Current Time is (" + (new Date().getTime() + rand + i) + ") :: " + new Date());
 		out.println(" " + "Sending message :: " + message.getText());
 		queueSender.send(message);
 		
 		if (rollBackFlag && (i == 3)) {
 			throw new Exception("Throwing Exception");
 		}
 }
	}
	
	private void closeJMS() {
		try {
			if (queueSession != null) {
				queueSession.close();
			}
			if (queueConnection != null) {
				queueConnection.close();
			}
		} catch (Exception e) {
			out.println(" ");
			e.printStackTrace(out);
		}
	}
	
	public void printQueue(String desc) {
		try {
			out.println( " " + desc + " Queue contents :: " );
			QueueBrowser browser = queueSession.createBrowser(queue);
			Enumeration<TextMessage> en = browser.getEnumeration();
			while (en.hasMoreElements()) {
			 TextMessage queueBrMessage = en.nextElement();
			 out .println( " " + queueBrMessage.getText());
			}
		} catch (JMSException e) {
			out.println(" ");
			e.printStackTrace(out);
		}
	}
	
	public void initQueue() throws Exception {
		InitialContext ctx = getInitialContext();
		
		queueConnectionFactory = (XAQueueConnectionFactory) ctx.lookup("jmsfactory/default/VQConFactoryXA");
		queue = (Queue) ctx.lookup("jmsqueues/default/VQueue");
 
		queueConnection = queueConnectionFactory.createXAQueueConnection();
		queueSession = queueConnection.createQueueSession(false, Session.AUTO_ACKNOWLEDGE);
		
		queueSender = queueSession.createSender(queue);
		queueConnection.start();
	}
	
	public InitialContext getInitialContext() throws Exception {
		Properties properties = new Properties();
		properties.put(Context.INITIAL_CONTEXT_FACTORY, "com.sap.engine.services.jndi.InitialContextFactoryImpl");
		properties.put(Context.PROVIDER_URL, "localhost:50004");
		properties.put(Context.SECURITY_PRINCIPAL, "Administrator");
		properties.put(Context.SECURITY_CREDENTIALS, "atlas123");
		properties.put("force_remote", "true");
		InitialContext context = new InitialContext(properties);
		return context;
	}
}

Any glitches in my code???

I would say there is a "glitch" in your design. Stuffing all of this transactional code in a servlet is questionable and in conflict with standard three-tier programming model.

Presentation tier

Business tier

Integration tier

Java servlets are for handling Presentation-oriented requirements via web server. Cramming business logic/data logic/transactional logic into servlet classes typically is not a very good design for anything mildly complex, e.g. distributed transactions.

I created this test servlet just to test the application and do a POC