com.isomorphic.jpa

Class EMFProviderCMT

com.isomorphic.jpa.EMFProviderCMT

All Implemented Interfaces:

EMFProviderInterface

public class EMFProviderCMT
implements EMFProviderInterface

EMF provider for Container Managed Transactions (CMT).

Use this provider if you want to use JPA data source in EJB environment (accessing JPA data source from enterprise bean). Values from jpa.entityManager and jpa.entityManagerFactory properties are used to locate EntityManager and EntityManagerFactory in container's environment context via JNDI. For this implementation to work persistence-context-ref and persistence-unit-ref should be declared for enterprise bean in /META-INF/ejb-jar.xml. For example:

 <?xml version="1.0" encoding="UTF-8"?>
 <ejb-jar
      version = "3.0"
      xmlns = "http://java.sun.com/xml/ns/javaee"
      xmlns:xsi = "http://www.w3.org/2001/XMLSchema-instance"
      xsi:schemaLocation = "http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/ejb-jar_3_0.xsd">
      <enterprise-beans>
          <session>
              <ejb-name>TestEJB</ejb-name>
              <persistence-context-ref>
                  <persistence-context-ref-name>REFERENCE_TO_ENTITY_MANAGER</persistence-context-ref-name>
                  <persistence-unit-name>PERSISTENCE_UNIT_NAME</persistence-unit-name>
              </persistence-context-ref>
              <persistence-unit-ref>
                  <persistence-unit-ref-name>REFERENCE_TO_ENTITY_MANAGER_FACTORY</persistence-unit-ref-name>
                  <persistence-unit-name>PERSISTENCE_UNIT_NAME</persistence-unit-name>
              </persistence-unit-ref>
         </session>
     </enterprise-beans>
 </ejb-jar>
 

getTransaction() will return instance of EJBContext located in "java:comp/EJBContext" in JNDI. Transaction will be committed by container. To roll back transaction EJBContext.setRollbackOnly() is used.

Field Summary

Fields

Modifier and Type	Field and Description
java.lang.String	entityManagerFactoryRef Name of the reference to managed entity manager factory.
java.lang.String	entityManagerRef Name of the reference to container managed entity manager.

Fields inherited from interface com.isomorphic.jpa.EMFProviderInterface

ENTITY_MANAGER, ENTITY_MANAGER_FACTORY, JPA_ENTITY_MANAGER, JPA_ENTITY_MANAGER_FACTORY, JPA_PERSISTENCE_UNIT_NAME, JPA_TRANSACTION, PERSISTENCE_UNIT_NAME, TRANSACTION

Constructor Summary

Constructors

Constructor and Description
EMFProviderCMT() Creates new EMF provider.
EMFProviderCMT(java.util.Properties config) Creates new EMF provider.
EMFProviderCMT(java.lang.String entityManagerRef, java.lang.String entityManagerFactoryRef) Creates new EMF provider with specified context reference names.

Method Summary

Methods

Modifier and Type	Method and Description
void	commitTransaction(java.lang.Object tx) Does nothing - container will commit transaction.
javax.persistence.EntityManagerFactory	get() Returns EntityManagerFactory found in container's environment context.
javax.persistence.EntityManager	getEntityManager() Returns EntityManager found in container's environment context.
java.lang.Object	getTransaction(javax.persistence.EntityManager em) Returns EJBContext found in container's environment context.
void	returnEntityManager(javax.persistence.EntityManager em) Does nothing - container will close EntityManager.
void	rollbackTransaction(java.lang.Object tx) Sets rollback flag for transaction by tx.setRollbackOnly().

Field Detail

entityManagerRef

public java.lang.String entityManagerRef

Name of the reference to container managed entity manager.

entityManagerFactoryRef

public java.lang.String entityManagerFactoryRef

Name of the reference to managed entity manager factory.

Constructor Detail

EMFProviderCMT

public EMFProviderCMT()

Creates new EMF provider. Values from jpa.entityManager and jpa.entityManagerFactory properties are used to locate EntityManager and EntityManagerFactory in container's environment context.

EMFProviderCMT

public EMFProviderCMT(java.util.Properties config)

Creates new EMF provider. Values from provided properties entityManager and entityManagerFactory are used to locate EntityManager and EntityManagerFactory in container's environment context.

Parameters:

config - Properties for provider configuration.

EMFProviderCMT

public EMFProviderCMT(java.lang.String entityManagerRef,
              java.lang.String entityManagerFactoryRef)

Creates new EMF provider with specified context reference names.

Parameters:

entityManagerRef - String name of context reference to entity manager.

entityManagerFactoryRef - String name of context reference to entity manager factory.

Method Detail

get

public javax.persistence.EntityManagerFactory get()

Returns EntityManagerFactory found in container's environment context.

Specified by:

get in interface EMFProviderInterface

Returns:

EntityManagerFactory can be used to acquire meta-data (for JPA 2.0) or implement "application managed entity manager" pattern.

getEntityManager

public javax.persistence.EntityManager getEntityManager()
                                                 throws javax.persistence.PersistenceException

Returns EntityManager found in container's environment context.

Specified by:

getEntityManager in interface EMFProviderInterface

Returns:

EntityManager for persistence operations.

Throws:

javax.persistence.PersistenceException - if unable to acquire EntityManager.

returnEntityManager

public void returnEntityManager(javax.persistence.EntityManager em)

Does nothing - container will close EntityManager.

Specified by:

returnEntityManager in interface EMFProviderInterface

Parameters:

em - EntityManager which should be closed.

getTransaction

public java.lang.Object getTransaction(javax.persistence.EntityManager em)
                                throws java.lang.Exception

Returns EJBContext found in container's environment context.

Specified by:

getTransaction in interface EMFProviderInterface

Parameters:

em - EntityManager needed if joining to existing transaction or null.

Returns:

Object Transaction for persistence operations.

Throws:

javax.persistence.PersistenceException - if unable to acquire or open transaction.

java.lang.Exception - if unable to acquire or open transaction.

commitTransaction

public void commitTransaction(java.lang.Object tx)
                       throws java.lang.Exception

Does nothing - container will commit transaction.

Specified by:

commitTransaction in interface EMFProviderInterface

Parameters:

tx - Object transaction to be commited.

Throws:

java.lang.Exception - occured while committing transaction.

rollbackTransaction

public void rollbackTransaction(java.lang.Object tx)

Sets rollback flag for transaction by tx.setRollbackOnly().

Specified by:

rollbackTransaction in interface EMFProviderInterface

Parameters:

tx - Object transaction to be rolled back.