openjpa-users mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From Rick Curtis <curti...@gmail.com>
Subject Re: Container Managed EntityManager - is there a chance to control flush calls ?
Date Mon, 11 Aug 2014 19:11:19 GMT
Yes OpenJPA will occasionally flush when/if it is deemed necessary. One
example that comes to mind is the openjpa.FlushBeforeQueries property[1]...
I'm sure there are others, but I can't come up with all of the different
ones.

The thing that concerns me is that you have Entities that aren't really
Entities... is there a reason why these things that shouldn't be persisted
aren't just treated as POJOs? It seems that might be a better way to go so
then you won't have to fake OpenJPA out.

[1]
http://ci.apache.org/projects/openjpa/trunk/docbook/manual.html#openjpa.FlushBeforeQueries


On Mon, Aug 11, 2014 at 1:55 PM, Christoph Weiss <christoph.weiss@de.ibm.com
> wrote:

> Hi Rick,
>
> Thanks for your reply!
> Well actually we do not have any "unwanted flush calls" but we are scared
> that they might happen ; )
>
> But let's take about the details:
> We try to upgrade an old JEE application (with an custom developed
> PersistenceFramework) to JPA.
> Because of effort and QA reason we want to maintain the old "business
> logic".  Here we had objects which are created, modified but never stored
> in the database.
> However those objects are now becoming JPAEntities and so we implemented
> our own UpdateManager. This UpdateManager is taking care that only
> "selected" objects are flushed.
> (as written in one of the previous posts).
>
> The complete concept and implementation is working fine as long as we can
> control when the flush is executed (--> goal "at the end of our EJB
> transaction")
> However talking to colleagues I understand that the EntityManager might do
> flush operations beside the transactions.  Reason could be e.g. to free up
> cache or memory.
> And that is something we want to avoid.
>
> Now I am not sure if this are just "rumors" from the colleagues or if
> there are cases where the EntityManager might execute a flush w/o any
> association / trigger from a transaction.
> Can you help on this topic?
>
> Cheers
> Christoph
>
>
>
>
>
>
>
>
>
>
> From:   Rick Curtis <curtisr7@gmail.com>
> To:     users <users@openjpa.apache.org>
> Date:   11.08.2014 20:38
> Subject:        Re: Container Managed EntityManager - is there a chance to
> control flush calls ?
>
>
>
> Nothing immediately comes to my mind. Perhaps a better explanation of what
> you are trying to do will expose some other solution. One question though,
> what is currently driving the unwanted flush() calls?
>
> Thanks,
> Rick
>
>
> On Mon, Aug 11, 2014 at 1:24 PM, Christoph Weiss
> <christoph.weiss@de.ibm.com
> > wrote:
>
> > Dear Community,
> >
> > We are running OpenJPa with "container managed" EntityManagers (using
> > WebSphere Application Server).
> > Because of technical reasons we want to explicitly control when the
> > EntityManager executes the flush.
> >
> > First I thought that the parameter "FlushMode" could be a solution, but
> > reading the documentation I understood it isn't.
> > So is there any other way to really control when the flush is executed?
> >
> > Any reply is appreciated. Thanks for your help in advance!
> >
> > Cheers
> > Christoph Weiss
> >
>
>
>
> --
> *Rick Curtis*
>
>


-- 
*Rick Curtis*

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