## Uses of Class
javax.persistence.PersistenceException

Packages that use PersistenceException
javax.persistence: Java Persistence is the API for the management for persistence and object/relational mapping.

### Uses of PersistenceException in javax.persistence

Subclasses of PersistenceException in javax.persistence
`class` `EntityExistsException` Thrown by the persistence provider when `EntityManager.persist(Object)` is called and the entity already exists.
`class` `EntityNotFoundException` Thrown by the persistence provider when an entity reference obtained by `EntityManager.getReference` is accessed but the entity does not exist.
`class` `LockTimeoutException` Thrown by the persistence provider when an pessimistic locking conflict occurs that does not result in transaction rollback.
`class` `NonUniqueResultException` Thrown by the persistence provider when `Query.getSingleResult()` or `TypedQuery.getSingleResult()` is executed on a query and there is more than one result from the query.
`class` `NoResultException` Thrown by the persistence provider when `Query.getSingleResult()` or `TypedQuery.getSingleResult()`is executed on a query and there is no result to return.
`class` `OptimisticLockException` Thrown by the persistence provider when an optimistic locking conflict occurs.
`class` `PessimisticLockException` Thrown by the persistence provider when an pessimistic locking conflict occurs.
`class` `QueryTimeoutException` Thrown by the persistence provider when a query times out and only the statement is rolled back.
`class` `RollbackException` Thrown by the persistence provider when `EntityTransaction.commit()` fails.
`class` `TransactionRequiredException` Thrown by the persistence provider when a transaction is required but is not active.