Hi Ken. This is a known issue -- one-to-many owned relationships of the same
kind aren't persisted correctly. We do plan to address this particular issue
in a forthcoming update. In the meantime though, you can look into using
unowned relationships (list of keys) instead which should work.
- Jason
On Thu, Sep 10, 2009 at 9:23 AM, Ken <kenot...@gmail.com> wrote:
>
> I have a JDO class representing a tree of entities, somewhat like
> this:
>
> public class TreeNode {
> private String nodeName;
> private List<TreeNode> children;
> ...
> }
>
> When I persist any such node to the datastore, the insert fails
> silently. The key of the object returned from makePersistent is null,
> and no entities reside in the data viewer.
>
> However, If I remove the 'children' field, or replace it with a list
> of keys, then objects may be persisted, but I get a chicken-and-egg
> problem when trying to create the entity key relationship, as the
> child key is not available until its entity is persisted, which means
> I cannot set the parent key on the child key after it has been
> persisted.
>
> Is this the expected behavior of the datastore? Are classes w/ fields
> of the same type allowed? How would one persist a tree otherwise,
> maintaining proper entity key parent/child relationships to ensure the
> whole tree is available in a transaction?
> >
>
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