javax.persistence
Interface EntityManagerFactory

public interface EntityManagerFactory

The EntityManagerFactory interface is used to interact with the entity manager factory for a 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:

Java Persistence API 1.0

Method Summary

void	close() Close the factory, releasing any resources that it holds.
EntityManager	createEntityManager() Create a new EntityManager.
EntityManager	createEntityManager(java.util.Map map) Create a new EntityManager with the specified Map of properties.
Cache	getCache() Access the cache that is associated with the entity manager factory(the "second level cache").
java.util.Map	getProperties() Get the properties and associated values that are in effect for the entity manager factory.
QueryBuilder	getQueryBuilder() Return an instance of QueryBuilder for the creation of Criteria API QueryDefinition objects.
java.util.Set<java.lang.String>	getSupportedProperties() Get the names of the properties that are supported for use with the entity manager factory.
boolean	isOpen() Indicates whether or not this factory is open.

Method Detail

createEntityManager

EntityManager createEntityManager()

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

createEntityManager

EntityManager createEntityManager(java.util.Map map)

Create a new 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.

getQueryBuilder

QueryBuilder getQueryBuilder()

Return an instance of QueryBuilder for the creation of Criteria API QueryDefinition objects.

Returns:

QueryBuilder instance

Throws:

java.lang.IllegalStateException - if the entity manager factory has been closed.

Since:

Java Persistence API 2.0

close

void close()

Close the factory, releasing any resources that it holds. After a factory instance is closed, all methods invoked on it will throw an 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.

isOpen

boolean isOpen()

Indicates whether or not this factory is open. Returns true until a call to close has been made.

getProperties

java.util.Map 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

Since:

Java Persistence API 2.0

getSupportedProperties

java.util.Set<java.lang.String> getSupportedProperties()

Get the names of the properties that are supported for use with the entity manager factory. These correspond to properties that may be passed to the methods of the EntityManagerFactory interface that take a properties argument. These include all standard properties as well as vendor-specific properties supported by the provider. These properties may or may not currently be in effect.

Returns:

properties and hints

Since:

Java Persistence API 2.0

getCache

Cache getCache()

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

Returns:

instance of the Cache interface

Throws:

java.lang.IllegalStateException - if the entity manager factory has been closed.

Since:

Java Persistence API 2.0