I created an application that has EJB3 and Hibernate3. Initially I was jus calling the method in Dao layer from EJB and there for every method get new hibernate session and do the transaction and so on...
Now i hav ben asked to do all the transaction from EJB layer itself. I have no clue how to begin with the same. i am using stateless session beans. and MySql database.
I am not able to undestarnd that is it necessary to use persistance.xml. Initially I was using hibernate.cfg.xml. If yes where am i going to map hbm.xml mapping and how to call the session
please its really urgent
See my first reply. The mechanism is called container managed transactions and is one of the basics of EJBs. I would strongly recommend you go through the linked tutorial before doing much more with EJBs. It will make your life much easier if you have a good grasp of the basics