Injecting EntityManager or passing it

[klind]

Hi... design question.

When using a SessionBean and some DAO classes, should i then inject EntityManager in all dao classes or pass it as a variable. ?

My SessionBean is injecting the EntityManager. I have read different opinions about this.

If I use a transaction started in my SessionBean, I would guess I should use the same EntityManager in that transaction. ? Hence passing it to the DAO classes. ?

Or can the container keep track of it if I inject my DAO classes and inject the EntityManager in the DAO class, and do not pass it ??

[wdfink]

I would keep DAO classes clean and did not use EntityManager here.

If you use EJB3 and JPA I would use the JPA classes, or if not wanted you may create the DAO inside the SLSB or JPA class.