openjpa-users mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From Daryl Stultz <da...@6degrees.com>
Subject Re: EntityManager used in multiple threads
Date Fri, 18 Sep 2009 13:51:45 GMT
On Fri, Sep 18, 2009 at 9:40 AM, C N Davies <cnd@cndavies.com> wrote:

> I was only commenting on the point you made regarding
>
>
I think we're talking about different coding patterns. With a managed entity
(in a long transaction or a case with only one em), you can call
em.refresh(object), but this returns a new instance of the class. I'm
talking about a way to push the values from a fresh instance into an
existing one.

So:

final A a = em.find(A.class, 1);
em.close(); // a is detached
...
em = getEm();
A a1 = em.find(A.class, a.getId()); // a1 is managed and fresh
JpaUtils.merge(a, a1); // copy from fresh to detached

The merge method here would copy properties from a1 to a, thus preserving
a's "final" modifier.

-- 
Daryl Stultz
_____________________________________
6 Degrees Software and Consulting, Inc.
http://www.6degrees.com
mailto:daryl@6degrees.com

Mime
  • Unnamed multipart/alternative (inline, None, 0 bytes)
View raw message