Hi,

First of all, thanks for posting, it really helps me.

objectuser  : Good post and the link was really nice.
Albert Attard  : Thanks for the examples, it shows that you have to
wright lots of code to manage your own relationships (which I was
trying to avoid).
leszek: This is what I did and I was trying to avoid to handle
persistence issues as much as I could.

I will re-model and start over and see how I should go on.

Thanks.

FF


On Sep 1, 9:52 am, leszek <[email protected]> wrote:
> You can follow something like that
>
> class Parent {
>   ....
>   @Persistent
>   private List<Long/Key> childList;
>
>   // non Persistent
>   private List<Child> list;
>   ...
>
> }
>
> class Child {
>
>   �...@primarykey
>    private Long/Key key;
>    ...
>
> }
>
> // before save Parent
>   private void beforeSave(EntityManager em,Parent pa) {
>      if (pa.getList() != null) {
>        List<Long> chList = new ArrayList<Long>();
>        for (Child ch : pa.getList) {
>          pm.makePersistent(ch);
>          pm.flush();
>          chList.add(ch.getKey());
>        }
>        pa.setChildList(chList);
>     }
>   }
>
>   private void afterLoad(EntityManager em,Parent pa)  {
>     List<Child> chList = new ArrayList<Child>();
>     for (Long key : pa.getChildList()) {
>        Child ch = pm.getObjectById(Child.class,key);
>        chList.add(ch);
>     }
>     pa.setList(chList);
>   }
>
>   PersistenManager pm;
>   ....
>
>   // main service
>   Parent pa = pm..getObjectById(...)
>   afterLoad(pm,pa);
>   ...
>   ...
>   beforeSave(pm,pa);
>   pm.makePersistent(pa);
>
>   List<Parent> pList = pm.queryExecute();
>   for (Parent pa : pList) {
>     afterLoad(pm,pa);
>   }
>   ...
>   // etc
>
> In order to avoid repeating the same beforeSave and afterLoad for all
> Entity classes having "onowned" relationship you can apply Annotation
> and, by  the use of reflection, develop generic approach for all
> classes having this feature.
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