This is a newbie question, I suppose, but I have the next question:
Is it consider a detached object and object create with a "new" operation and then assigns to it a identifer that exists in the database? Can I invoke session.lock() or session.update() in order to reattach the object to the session?



Thanks in advance,

Roque

Is the same thing of a detached object modified outside the session and then reattached.

You have got an error?

No, I don't have any error. But I wonder what's the different, if it exists, between a detached object and one created in that way.
What are the benefits of maintaining a detached object, for example in the HttpSession, and reattaching later to the session instead of creating a new one and associating a valid id in order to make a delete or update operation?

For a delete there is no difference I think.
For an update you have to manual recreate all properties.
This can be dangerous: if you update an empty object with only the id setted then all DB fields mapped will be setted to null (also collections)