org.datanucleus.api.jpa

Class NucleusJPAHelper

java.lang.Object

org.datanucleus.api.jpa.NucleusJPAHelper

public class NucleusJPAHelper
extends Object

Helper for persistence operations with JPA.

Field Summary

Fields

Modifier and Type	Field and Description
protected static org.datanucleus.util.Localiser	LOCALISER Localisation utility for output messages

Constructor Summary

Constructors

Constructor and Description
NucleusJPAHelper()

Method Summary

Methods

Modifier and Type	Method and Description
static String[]	getDirtyFields(Object obj, javax.jdo.PersistenceManager em) Accessor for the names of the dirty fields of the persistable object.
static javax.persistence.EntityManager	getEntityManager(Object obj) Accessor for the EntityManager for the supplied (persistable) object.
static javax.jdo.spi.JDOImplHelper	getJDOImplHelper() Get the JDOImplHelper instance.
static javax.persistence.PersistenceException	getJPAExceptionForJDOException(javax.jdo.JDOException jdoe) Convenience method to convert a JDO exception into a JPA exception.
static javax.persistence.PersistenceException	getJPAExceptionForNucleusException(org.datanucleus.exceptions.NucleusException ne) Convenience method to convert a Nucleus exception into a JPA exception.
static String[]	getLoadedFields(Object obj, javax.persistence.EntityManager em) Accessor for the names of the loaded fields of the persistable object.
static String	getObjectState(Object obj) Convenience method to return a string of the state of an object.
static boolean	isDeleted(Object obj) Convenience accessor for whether the object is deleted.
static boolean	isDetached(Object obj) Convenience accessor for whether the object is detached.
static boolean	isPersistent(Object obj) Convenience accessor for whether the object is persistent.
static boolean	isTransactional(Object obj) Convenience accessor for whether the object is transactional.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

LOCALISER

protected static final org.datanucleus.util.Localiser LOCALISER

Localisation utility for output messages

Constructor Detail

NucleusJPAHelper

public NucleusJPAHelper()

Method Detail

getEntityManager

public static javax.persistence.EntityManager getEntityManager(Object obj)

Accessor for the EntityManager for the supplied (persistable) object. If the object is detached or transient then returns null.

Parameters:

obj - The persistable object

Returns:

The entity manager for this object

isPersistent

public static boolean isPersistent(Object obj)

Convenience accessor for whether the object is persistent.

Parameters:

obj - The object

Returns:

Whether it is persistent

isDeleted

public static boolean isDeleted(Object obj)

Convenience accessor for whether the object is deleted.

Parameters:

obj - The object

Returns:

Whether it is deleted

isDetached

public static boolean isDetached(Object obj)

Convenience accessor for whether the object is detached.

Parameters:

obj - The object

Returns:

Whether it is persistent

isTransactional

public static boolean isTransactional(Object obj)

Convenience accessor for whether the object is transactional.

Parameters:

obj - The object

Returns:

Whether it is transactional

getObjectState

public static String getObjectState(Object obj)

Convenience method to return a string of the state of an object. Will return things like "detached", "persistent", etc

Parameters:

obj - The object

Returns:

The state

getDirtyFields

public static String[] getDirtyFields(Object obj,
                      javax.jdo.PersistenceManager em)

Accessor for the names of the dirty fields of the persistable object.

Parameters:

obj - The persistable object

em - The Entity Manager (only required if the object is detached)

Returns:

Names of the dirty fields

getLoadedFields

public static String[] getLoadedFields(Object obj,
                       javax.persistence.EntityManager em)

Accessor for the names of the loaded fields of the persistable object.

Parameters:

obj - Persistable object

em - The Entity Manager (only required if the object is detached)

Returns:

Names of the loaded fields

getJPAExceptionForJDOException

public static javax.persistence.PersistenceException getJPAExceptionForJDOException(javax.jdo.JDOException jdoe)

Convenience method to convert a JDO exception into a JPA exception. If the incoming exception has a "failed object" then create the new exception with a failed object. Otherwise if the incoming exception has nested exceptions then create this exception with those nested exceptions. Else create this exception with the incoming exception as its nested exception. TODO When our JPA impl doesnt depend on JDO remove this

Parameters:

jdoe - JDOException

Returns:

The JPAException

getJPAExceptionForNucleusException

public static javax.persistence.PersistenceException getJPAExceptionForNucleusException(org.datanucleus.exceptions.NucleusException ne)

Convenience method to convert a Nucleus exception into a JPA exception. If the incoming exception has a "failed object" then create the new exception with a failed object. Otherwise if the incoming exception has nested exceptions then create this exception with those nested exceptions. Else create this exception with the incoming exception as its nested exception.

Parameters:

ne - NucleusException

Returns:

The JPAException

getJDOImplHelper

public static javax.jdo.spi.JDOImplHelper getJDOImplHelper()

Get the JDOImplHelper instance. This must be done in a doPrivileged block.

Returns:

The JDOImplHelper.