Bypassing the Hibernate cache in a transaction

Question

I have a strange use case of Hibernate where in a call farther up a large stack needs an unmodified copy of an object that is part of a hibernate transaction. however, every time I ask Hibernate for a copy of the object, it's returning the version that's already been modified / is part of the transaction.

Is there a way for me to force Hibernate to return the db copy / uncached version of object in question?

Answer 1

Open a new Session and get the copy of the object from the new Session.

Answer 2

Session#refresh(Object object);

Re-read the state of the given instance from the underlying database.

or you can call session.evict(obj) (removes it from the session cache) and load() it afresh.

Note that if you are using EntityManager instead of Session, you won't have the evict() method. You can obtain the Session this way:

Session session = (Session) entityManager.getDelegate();