I am a little bit confused at what you exactly mean with
"I cant use injection ,so i need to create entity manager by using in factory.createEntityManager.
The issue here that i need in the same transaction (i use JTA) to share the same persistence context (entity manager)."
Does this mean you don't want to use injection? or that you think JBoss can't inject for you?
And then you say you need a single transaction to share the same persistence context. Kind o fconsufising, but anyway,
It might be that you are looking for an extended persistence context. If I am correct you can use the LocalThread for that or use the Open Session in view pattern here http://www.hibernate.org/43.html.