Ok, thank you. Hopefully i can get it to work :)

//Morten

On Fri, May 15, 2009 at 15:32, <[email protected]> wrote:

> Hi,
>
> best, you have a look at the documentation:
>
>
> http://people.apache.org/~mprudhom/openjpa/site/openjpa-project/manual/ref_guide_pc_enhance.html<http://people.apache.org/%7Emprudhom/openjpa/site/openjpa-project/manual/ref_guide_pc_enhance.html>
>
> OpenJPA classes need to be enhanced to provide lazy fetching. Else there
> will always been used eager fetching, which could be the cause of your
> problem.
>
> -------- Original-Nachricht --------
> > Datum: Fri, 15 May 2009 15:26:43 +0200
> > Von: "Morten O. Hansen" <[email protected]>
> > An: [email protected]
> > Betreff: Re: Creating nodes with parents
>
> > Hi
> >
> > Thank for your quick response :) Sorry for my ignorance, but what do you
> > mean by enhancing the classes?
> >
> > //Morten
> >
> > On Fri, May 15, 2009 at 15:21, <[email protected]> wrote:
> >
> > > Hi,
> > >
> > > as far as I know, TopLink has a maximum fetching depth of 2 by default
> > and
> > > OpenJPA has an infinite fetching depth, which could lead to recursions
> > in
> > > the worst case if you use eager fetching.
> > > I am wondering why this also happens with lazy fetching - did you
> forget
> > to
> > > enhance your classes?
> > >
> > > You can set the maximum fetching depth in your persistence.xml by
> > setting
> > > the following property:
> > >
> > > <property name="openjpa.MaxFetchDepth" value="2"/>
> > >
> > > I hope this helps :)
> > >
> > > -------- Original-Nachricht --------
> > > > Datum: Fri, 15 May 2009 14:58:03 +0200
> > > > Von: "Morten O. Hansen" <[email protected]>
> > > > An: [email protected]
> > > > Betreff: Creating nodes with parents
> > >
> > > > Hi all
> > > >
> > > > I'm trying to create a Node class, where every Node has a pointer to
> a
> > > > parent Node (or null if there is none).
> > > >
> > > > A simplified view of the Node-class looks like this:
> > > >
> > > > @Entity
> > > > public class Node {
> > > >   @Id protected long id;
> > > >   @ManyToOne(fetch=LAZY)
> > > >   protected Node parent;
> > > >   protected String name;
> > > >   protected String displayName;
> > > >
> > > > // setters / getters..
> > > > }
> > > >
> > > > And this was working correctly in TopLink (I think they just do
> > infinite
> > > > recursion depth), but in OpenJPA i get something that looks like
> > > recursion
> > > > errors.
> > > >
> > > > Is there a better way of doing this? I have implemented a hack just
> > using
> > > > long parentId instead, but that kinda sucks when you are deleting and
> > > > updating nodes.
> > > >
> > > > I know there is something called FetchGroups in OpenJPA, but i
> > couldn't
> > > > really get them to work and I want to have entities that hopefully
> > isn't
> > > > tied down to OpenJPA.
> > > >
> > > > --
> > > > Morten
> > >
> > > --
> > > Neu: GMX FreeDSL Komplettanschluss mit DSL 6.000 Flatrate +
> > > Telefonanschluss für nur 17,95 Euro/mtl.!*
> > > http://dslspecial.gmx.de/freedsl-surfflat/?ac=OM.AD.PD003K11308T4569a
> > >
>
> --
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