JPA Interface

EntityManagerFactory

Interface used to interact with the entity manager factory for the persistence unit.

When the application has finished using the entity manager factory, and/or at application shutdown, the application should close the entity manager factory. Once an EntityManagerFactory has been closed, all its entity managers are considered to be in the closed state.

Since:: JPA 1.0

The Database Connection using JPA article explains how to use EntityManagerFactory.

Public Methods

Add a named copy of the EntityGraph to the EntityManagerFactory.

If an entity graph with the same name already exists, it is replaced.

Parameters:: graphName - name for the entity graph; entityGraph - entity graph

Since:: JPA 2.1

Define the query, typed query, or stored procedure query as a named query such that future query objects can be created from it using the createNamedQuery or createNamedStoredProcedureQuery method.

Any configuration of the query object (except for actual parameter binding) in effect when the named query is added is retained as part of the named query definition. This includes configuration information such as max results, hints, flush mode, lock mode, result set mapping information, and information about stored procedure parameters.

When the query is executed, information that can be set by means of the query APIs can be overridden. Information that is overridden does not affect the named query as registered with the entity manager factory, and thus does not affect subsequent query objects created from it by means of the createNamedQuery or createNamedStoredProcedureQuery method.

If a named query of the same name has been previously defined, either statically via metadata or via this method, that query definition is replaced.

Parameters:: name - name for the query; query - Query, TypedQuery, or StoredProcedureQuery object

Since:: JPA 2.1

Close the factory, releasing any resources that it holds.

After a factory instance has been closed, all methods invoked on it will throw the IllegalStateException, except for isOpen, which will return false. Once an EntityManagerFactory has been closed, all its entity managers are considered to be in the closed state.

Throws:: IllegalStateException - if the entity manager factory has been closed

Since:: JPA 1.0

Create a new application-managed EntityManager.

This method returns a new EntityManager instance each time it is invoked. The isOpen method will return true on the returned instance.

Return:: entity manager instance

Throws:: IllegalStateException - if the entity manager factory has been closed

Since:: JPA 1.0

Create a new application-managed EntityManager with the specified Map of properties.

This method returns a new EntityManager instance each time it is invoked. The isOpen method will return true on the returned instance.

Parameters:: map - properties for entity manager

Return:: entity manager instance

Throws:: IllegalStateException - if the entity manager factory has been closed

Since:: JPA 1.0

Create a new JTA application-managed EntityManager with the specified synchronization type.

This method returns a new EntityManager instance each time it is invoked. The isOpen method will return true on the returned instance.

Parameters:: synchronizationType - how and when the entity manager should be synchronized with the current JTA transaction

Return:: entity manager instance

Throws:: IllegalStateException - if the entity manager factory has been configured for resource-local entity managers or is closed

Since:: JPA 2.1

Create a new JTA application-managed EntityManager with the specified synchronization type and map of properties.

This method returns a new EntityManager instance each time it is invoked. The isOpen method will return true on the returned instance.

Parameters:: synchronizationType - how and when the entity manager should be synchronized with the current JTA transaction; map - properties for entity manager

Return:: entity manager instance

Throws:: IllegalStateException - if the entity manager factory has been configured for resource-local entity managers or is closed

Since:: JPA 2.1

Access the cache that is associated with the entity manager factory (the "second level cache").

Return:: instance of the Cache interface or null if no cache is in use

Throws:: IllegalStateException - if the entity manager factory has been closed

Since:: JPA 2.0

Return an instance of CriteriaBuilder for the creation of CriteriaQuery objects.

Return:: CriteriaBuilder instance

Throws:: IllegalStateException - if the entity manager factory has been closed

Since:: JPA 2.0

Return an instance of Metamodel interface for access to the metamodel of the persistence unit.

Return:: Metamodel instance

Throws:: IllegalStateException - if the entity manager factory has been closed

Since:: JPA 2.0

Return interface providing access to utility methods for the persistence unit.

Return:: PersistenceUnitUtil interface

Throws:: IllegalStateException - if the entity manager factory has been closed

Since:: JPA 2.0

Get the properties and associated values that are in effect for the entity manager factory.

Changing the contents of the map does not change the configuration in effect.

Return:: properties

Throws:: IllegalStateException - if the entity manager factory has been closed

Since:: JPA 2.0

Indicates whether the factory is open.

Returns true until the factory has been closed.

Return:: boolean indicating whether the factory is open

Since:: JPA 1.0

Return an object of the specified type to allow access to the provider-specific API.

If the provider's EntityManagerFactory implementation does not support the specified class, the PersistenceException is thrown.

Parameters:: cls - the class of the object to be returned. This is normally either the underlying EntityManagerFactory implementation class or an interface that it implements.

Return:: an instance of the specified class

Throws:: PersistenceException - if the provider does not support the call

Since:: JPA 2.1