On Apr 25, 2007, at 10:22 AM, Patrick Linskey wrote:
If I want to have generic code, how am I supposed to
implement the createNamedQuery method? Do I leave the EM
open forever? That doesn't seem right. So when am I
supposed to close the EM?
1. Create an EM proxy. You've already got one, so we're good there.
2. The EM proxy should create a new EM for each persistence
context. In
a tx, that means that it hangs onto the EM for the duration of the tx.
Outside a tx, that means that it keeps the EM open for the duration of
each operation.
For a find(), that's the duration of the stack execution.
For a query, that means you need to create a Query proxy also, and
hand
off the EM created during createQuery() to the Query proxy. Then, the
Query proxy is responsible for closing the EM after
Query.getResultList() / Query.getSingleResult() is exectued.
Ah. That is my problemo.
Thanks,
-dain
