Hibernate: How to fix "identifier of an instance altered from X to Y"?

Question

org.hibernate.HibernateException: identifier of an instance 
of org.cometd.hibernate.User altered from 12 to 3

in fact, my user table is really must dynamically change its value, my Java app is multithreaded. Any ideas how to fix it?

Answer 1

Are you changing the primary key value of a User object somewhere? You shouldn't do that. Check that your mapping for the primary key is correct.

What does your mapping XML file or mapping annotations look like?

Answer 2

You must detach your entity from session before modifying its ID fields

Answer 3

In my case, the PK Field in hbm.xml was of type "integer" but in bean code it was long.