Thanks a lot I really appreciate the answer. I was not so confused after all :-)
As soon as I am trying to use a WebSphere MQ XA connection factory, my MDB never receive any messages. Any pointers on which JBoss classes I should look at/trace through to understand where the problem might be? I do believe that it is an MDB related problem since I am able to do 2PC with a WebSphere MQ queue using an XA connection factory when it is done from within the MDB onMessage method (I configured an XA connector like the JmsXA one but for WS MQ). Thomas -----Original Message----- From: hiram [mailto:[EMAIL PROTECTED] Sent: Monday, June 09, 2003 6:43 PM To: [EMAIL PROTECTED] Subject: Re: [JBoss-user] XA connection factory for an MDB Hi Thomas, [EMAIL PROTECTED] wrote: > My limited knowledge of MDB internals and XA is getting me confused. > > The basic question that I have is "for what purpose do I need an XA > connection factory for an MDB?" > To get a 2 phase commit between all the resources involved in the tranasaction. > Initially, my answer was as follow: If I deploy my MDB with container > managed transaction and transaction required, and if the implementation > of my onMessage method is accessing an external resource that I want to > synchronize through XA with the reading of the message by the MDB, then > I need the MDB to use an XA connection factory (so all the resources > involved in the transaction are XA "enabled"). > yes you are correct. > I did some testing with JBoss and it seems that even if my MDB is not > using an XA transaction, everything is working ok: > > - I have a MDB listening to a WebSphere MQ queue and not using > an XA connection factory. > good job. > - My onMessage operation is sending a message to a JBoss queue > in a transacted session using the JmsXA connection factory. > > - If I generate an abort in my onMessage method > (mdbContext.setRollbackOnly ()), then the rollback is done on the JBoss > queue and on the MDB queue. > That is correct. The JBoss MDB contaier was created knowing that it would not allways be able to work with an XA connection to get it's messages. If the MDB does not have XA jms provider, it will manually commit/rollback the jms transaction (using Session.commit()/Session.rollback()). > So, either I do not need an XA connection factory for my MDB (and then > is there any cases where I will need one), either the fact that it is Not strictly needed. > working on JBoss is for some kind of other reason and I am not doing > true XA between the MDB queue and the JBoss one and in some cases > (according to where/when the abort is occurring), my transaction > integrity between the 2 queues might not be respected. > That's exactly what is going on. The XA transaction is being commited/rolledback and then the MQSeries TX is being commited/rolledback. So you do run the risk of of lossing integrity. > Anyone with a good answer/explanation? > > Thomas > > Regards, Hiram ------------------------------------------------------- This SF.net email is sponsored by: Etnus, makers of TotalView, The best thread debugger on the planet. Designed with thread debugging features you've never dreamed of, try TotalView 6 free at www.etnus.com. _______________________________________________ JBoss-user mailing list [EMAIL PROTECTED] https://lists.sourceforge.net/lists/listinfo/jboss-user ------------------------------------------------------- This SF.net email is sponsored by: Etnus, makers of TotalView, The best thread debugger on the planet. Designed with thread debugging features you've never dreamed of, try TotalView 6 free at www.etnus.com. _______________________________________________ JBoss-user mailing list [EMAIL PROTECTED] https://lists.sourceforge.net/lists/listinfo/jboss-user
