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brendanl · Posted: Fri Sep 30, 2005 3:26 pm Post subject:

I've seen quite a few posts with some ideas that I have had a play with, but found no solution to my problem.

I need a transacted connection - so no messages are ever lost.
I need the support of an automatic backoutcount increment and redeliver
& I need the support of the automatic message forwarding to the backout queue.

From my many combinations of code, I have observed the following

untransacted Session createQueueSession(false, ...)
onMessage - throws RuntimeException
message is redelivered until max is reached then forwarded to backout queue.

However, as mentioned untransacted is no good - if the power goes off within onMessage, the message is lost.

So
Transacted Session - createQueueSession(true, ...)
onMessage - throws RuntimeException
Message is forward immediately to backoutqueue - there is no concept of redeliver until max is reached. And when the application is shutdown, the message is put back to the original queue.

This message back to the original queue behaviour would be related to the fact that its transacted and a commit was never issued

So
Within onMessage, I am now sending a commit command. So - its now transacted and messages dont return to the original queue from the backout once the app is turned off. However, the messages dont wait for the max retry count before they are put to the backout - there is no redeliver. I quess this is because the commit is somehow issued earlier??

What does it take to satisfy my requirements????
Heres some code if it helps. I also tried passing the session to the listener, but that didnt work to well either.

Thanks very much to all those that are able to offer some advice.

public class OnMessageReceiver {
public static void main(String[] args) {
OnMessageReceiver app = new OnMessageReceiver();
app.go();
}
public Object lock;
public void dowait() throws Exception{
synchronized(lock){
lock.wait();
}
}
public void unwait(){
synchronized(lock){
lock.notifyAll();
}
}
public void go(){
try{
System.out.println("starting");
MQJMSQueueConnectionFactory factory = new MQJMSQueueConnectionFactory();
factory.setTransportType(1);
factory.setQueueManager("localQM");
factory.setHostName("CORWCS0003");
factory.setPort(Integer.parseInt("1414"));
factory.setChannel("serverConnection");
lock = new Integer(1);

QueueConnection connection = factory.createQueueConnection();
QueueSession session = connection.createQueueSession (true, Session.AUTO_ACKNOWLEDGE);
connection.start();
QueueReceiver receiver = session.createReceiver(session.createQueue("MFP_REQUEST"));
MyListenerSimple listener = new MyListenerSimple(this);
receiver.setMessageListener(listener);
while(true){
dowait();
System.out.println("Commiting session");
session.commit();
}
//session.close();
//connection.close();

}catch(Exception e){
e.printStackTrace();
}
}
}

class MyListenerSimple implements javax.jms.MessageListener {
public OnMessageReceiver that;
MyListenerSimple(OnMessageReceiver that) {this.that = that;}

public void onMessage(javax.jms.Message msg) {

try{
System.out.println ("JMS client: received message ======> " + ((TextMessage)msg).getJMSMessageID() +" " + ((TextMessage)msg).getText());
that.unwait();

}catch(Exception e){e.printStackTrace();}
if(true){
System.out.println("throwing exception");
throw new RuntimeException("sss");
}

}
}