javax.persistence.EntityManagerFactory - JPA interface
javax.persistence
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
Learn how to use EntityManagerFactory in
Chapter 3 of the ObjectDB/JPA manual.
void
close()
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.
- Returns:
- entity manager instance
- Throws:
-
IllegalStateException- if the entity manager factory has been closed
- Since:
- JPA 1.0
EntityManager
createEntityManager(Map map)
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
- Returns:
- entity manager instance
- Throws:
-
IllegalStateException- if the entity manager factory has been closed
- Since:
- JPA 1.0
Access the cache that is associated with the entity manager factory (the "second level cache").
- Returns:
-
instance of the
Cacheinterface
- 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.
- Returns:
- 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.
- Returns:
- 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.
- Returns:
-
PersistenceUnitUtilinterface
- Throws:
-
IllegalStateException- if the entity manager factory has been closed
- Since:
- JPA 2.0
Map<String,Object>
getProperties()
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.
- Returns:
- properties
- Throws:
-
IllegalStateException- if the entity manager factory has been closed
- Since:
- JPA 2.0
boolean
isOpen()
Indicates whether the factory is open. Returns true until the factory has been closed.
- Returns:
- boolean indicating whether the factory is open
- Since:
- JPA 1.0
This documentation page is derived (with some adjustments) from the open source JPA 2 RI (EclipseLink)
and is available under the terms of the Eclipse Public License, v. 1.0 and Eclipse Distribution License, v. 1.0.
and is available under the terms of the Eclipse Public License, v. 1.0 and Eclipse Distribution License, v. 1.0.
Object Relational Mapping (ORM) JPA 2 providers include Hibernate, EclipseLink, TopLink, OpenJPA and DataNucleus.
ObjectDB is not an ORM JPA implementation but an Object Database for Java with built in JPA 2 support.
