T find(
  Class<T> entityClass,
  Object primaryKey,
  LockModeType lockMode,
  Map<String,Object> properties
)

Find by primary key and lock the entity, using the specified properties. Search for an entity of the specified class and primary key, and lock it with respect to the specified lock type. If the entity instance is contained in the persistence context, it is returned from there.

If the entity is found within the persistence context and the lock mode type is pessimistic and the entity has a version attribute, the persistence provider must perform optimistic version checks when obtaining the database lock. If these checks fail, the OptimisticLockException is thrown.

If the lock mode type is pessimistic and the entity instance is found but cannot be locked:

• the PessimisticLockException is thrown if the database locking failure causes transaction-level rollback
• the LockTimeoutException is thrown if the database locking failure causes only statement-level rollback

If a vendor-specific property or hint is not recognized, it is silently ignored.

Portable applications should not rely on the standard timeout hint. Depending on the database in use and the locking mechanisms used by the provider, the hint may or may not be observed.

Parameters:

entityClass - entity class

lockMode - lock mode

properties - standard and vendor-specific properties and hints

primaryKey - primary key

Returns:

the found entity instance or null if the entity does not exist.

Throws:

PessimisticLockException - if pessimistic locking fails and the transaction is rolled back.

LockTimeoutException - if pessimistic locking fails and only the statement is rolled back.

IllegalArgumentException - if the first argument does not denote an entity type or the second argument is not a valid type for that entity's primary key or is null.

PersistenceException - if an unsupported lock call is made.

OptimisticLockException - if the optimistic version check fails.

TransactionRequiredException - if there is no transaction and a lock mode other than NONE is specified or if invoked on an entity manager which has not been joined to the current transaction and a lock mode other than NONE is specified.

Since:

Jakarta Persistence (JPA) 2.0