When does Hibernate (2.1) update the version property of an object? Upon flush? Of course, I'm assuming that Hibernate keeps the object entity in sync with the DB by updating its version property with the new version set in the DB.
Oh, and that reminds me of another question: when using automatically generated ids, when does Hibernate set a new object's id? The moment save() returns or upon flush?

Thanks!

Try it and see. Your debugger is your friend :-)

Ha - my debugger = log.debug.
I've tried it a little, and am having a hard time pinning it down.
Please, if someone happens to know the answer to this question just jot it down real quick. :-)

version update occurs:
- on flush (so on commit too if flushmode = auto) if the versioned object has been updated (of course)
- when you work with detached object and use session.update()
- ...


why? what is your problem ?


note: for generated id ... it is when calling session.save()

don't forget all cascade aspect

and eclipse is a little bit better than ultraedit... easier to debug ;)

Thank you for the reply! We are using Hibernate persisted objects between application tiers (detach, serialize to other tier, other tier eventually sends changed objects back, etc). However, we are also trying to develop a solution where we don't have to retransmit the entire graph every time. This is complicated by the fact that the model (graph) mutates on save/update (on saves, the id is assigned, on updates, the version is changed) and so we have to keep these mutations in sync between tiers. Some applications can get away with the "load entire graph, let user make mods, save entire graph back to server - if user wants to continue editing, then reload entire graph from server" cycle, but that is not a workable option for us at the moment. We are now using an enterprise event system (ESB basically) whereby changes are transmitted live to other listening parties, thus keeping the tiers in sync. We just need to know the mechanics of when Hibernate mutates our objects so that we can properly sync those mutations with other tiers via the ESB.

Thanks!