JPA and default locking mode

Question

With JPA, we can use manually OPTIMISTIC or PESSIMISTIC locking to handle entity changes in transactions.

I wonder how JPA handles locking

Answer 1

In the specification persistence_2.0, page 89:

If a versioned object is otherwise updated or removed, then the implementation must ensure that the requirements of LockModeType.OPTIMISTIC_FORCE_INCREMENT are met, even if no explicit call to EntityManager.lock was made.