good references on J2EE transactions

[redhonda]

I have built an application that uses entity beans, session beans, JSPs, servlets, and JDBC to a single database. I want to increase the database accessing performance by creating transactions, cutting down on unnecessarly database hits. I have read books, online helps, and J2EE Blue Prints, but none does a good job in explaining in details of container managed and bean managed transactions, their advantages, problems, and the most of important of all, good *examples* illustrating all of the different scenarios. In fact, I am more confused after reading them.

Does anyone know of a single source that one *must* read in order to master the concepts of J2EE transaction for a confused beginner like me?

Thanks

[prilmeie]

Generally avoid user managed Transactions. That way your Application can no longer be extended in a non-trivial way.

The must significant gain you get when you use EJB is that you do not have to worry about transactions (and concurrency) during programming.

The only book I have is the Oreilly book "Enterprise Java Beans". One chapter discusses Transactions.