Quote Originally Posted by Ben Alex View Post
Because JPA is so heavily used in current enterprise Java apps, and it provides a persistence layer abstraction via the EntityManager interface, it is possible to provide an alternate implementation if required.
I've been using ROO for a while, the persistence layer generally works fine for me. However, my colleagues and I did found it makes testing of controllers and business service objects harder to test (harder to mock compare to a DAO pattern) due to the direct access to static domain methods. I'd wish a DAO pattern can be available besides default pattern in the ROO persistence layer.