Not really. You can use a value object that implemts optimistic locking (xdoclet will generate them for you). Then when you try to commit the changes, the value object realizes that the data has changed on the server and you get some sort of optimistic locking exception.
First of all, thanks for answering. Second, I didn't understand to well your solution with xdoclet. If you want, please detail.
There are J2EE patterns to deal with this problem such as using version number. If you need more help on this, let me know.
I've never used this my self, but XDoclet has an @ejb:bean use-soft-locking, which implements optimistic locking. Here is a link:
If you need more help, I suggest you ask on the XDoclet lists.
Thanks for help.
I think I've got the idea. Still, if you have more informations about J2EE Patterns and version number it will great.
Thank you, again.