Hi,

I've got a situation where I have set up appropriate cascading on associations to create them without having to worry about saving those objects directly, essentially allowing hibernate to do its stuff. This works well and I'm happy with that when my business code is in charge of the creation. However, on receiving a dettached domain object from another application, I only want to update the top level entity itself, only its base properties not any underlying associations, to limit any stupidity from the client. The update essentially pertains only to the inbound entity.

Currently, in the update method on my service I just do a lookup of the object from the db and copy the properties from the inbound object in to the looked up version and then allow the changes to flush. This means I am in control of which props get updated:



However as I am not reattaching the object to the session, this removes the ability to use Hibernate's automatic versioning and optimistic locking that could be achieved with reattaching.

Question is; is there any way to change the cascading settings based on the reattachement to only flush changes to the top level object? i.e. I am happy with my cascade settings when creating objects during a session and when I am in control, but don't want those cascades to apply on reattaching the object to a session.

Apologies on the long post, can't cut it down much smaller :)

Thanks

You may want to consider using inverse=true in the main object and let the many-to-one side of the relationship do the updates.

http://www.hibernate.org/hib_docs/v3/re ... ientupdate

I hope this helps :)

Marius

What do you mean? Does the detached object contain version data that you want to use?
As long as it doesn't you'll still have versioning and optimistic locking done by hibernate. The object's version was fetched when you loaded it, and it will be checked again when the session is flushed, to see that is wasn't changed in the meantime.

If you do want to use the detached object's version, you might consider using session.merge() or session.replicate(), but i'm not sure what's the purpose.

My assumption, which I should have tested, was that if a client was to mess about with the object graph of a detached object and hand back to my service that calls saveOrUpdate on the detached object to reattach it to the session, hibernate would try to reflect all changes made to the object, including any new associations.

As I have mapped all associations with inverse=true, that is not the case, and hibernate does exactly what I require; which is to only update the inbound entity's properties and any many-to-one relationships with cascade=all set.

Job Done,

Thanks