Hi. I don't account numbers that are to be seen by clients to be exactly the same as the given sequential id so I want to have another field that contains the id with some appended random numbers. But I don't know the id until I have saved the object to the database. After I have saved the object the then detached object contains the id and then I can make the new field. But then I can't declare that field as non-null which I would think would be pretty important. Also I have to make two hits to the database for one save.

Is there a better way to do this?

The save method returns the primary key, even before the transaction is comitted. You can get the primary key that is about to be used, and set your other properties, and then do the commit. You'll only end up with one transaction through one Hibernate Session.