Package org.datanucleus.api.jdo

Class DataNucleusHelperJDO

java.lang.Object

org.datanucleus.api.jdo.DataNucleusHelperJDO

public class DataNucleusHelperJDO
extends Object

Helper class for accessing DataNucleus internals from a JDO environment. This is a supplement to the JDO API class JDOHelper.

Constructor Summary

Constructors

Constructor	Description
DataNucleusHelperJDO()

Method Summary

Modifier and Type	Method	Description
static String[]	getClassesWithMetaData(javax.jdo.PersistenceManagerFactory pmf)	Accessor for the names of the classes that have MetaData for this PMF.
static org.datanucleus.identity.SingleFieldId	getDataNucleusIdentityForSingleFieldIdentity(javax.jdo.identity.SingleFieldIdentity sfid)
static Object[]	getDetachedStateForObject(Object obj)	Accessor for the jdoDetachedState field of a detached object.
static String[]	getDirtyFields(Object obj, javax.jdo.PersistenceManager pm)	Accessor for the names of the dirty fields of the persistable object.
static int[]	getFieldsInFetchPlanForClass(javax.jdo.PersistenceManager pm, String className)	Convenience accessor for the fields of a specified class that are currently in the FetchPlan.
static String[]	getLoadedFields(Object obj, javax.jdo.PersistenceManager pm)	Accessor for the names of the loaded fields of the persistable object.
static org.datanucleus.metadata.ClassMetaData	getMetaDataForClass(javax.jdo.PersistenceManagerFactory pmf, Class cls)	Accessor for the MetaData for the specified class
static String	getObjectIdClassForInputIdClass(String objectIdClass)
static JDOQueryCache	getQueryResultCache(javax.jdo.PersistenceManagerFactory pmf)	Convenience accessor for the query results cache.
static javax.jdo.identity.SingleFieldIdentity	getSingleFieldIdentityForDataNucleusIdentity(org.datanucleus.identity.SingleFieldId dnid, Class targetClass)	Method to convert a DataNucleus "identity" for a single-field application id type to the JDO provided SingleFieldIdentity type.
static Boolean	isFieldDirty(Object obj, String memberName, javax.jdo.PersistenceManager pm)	Accessor for whether the specified member (field/property) of the passed persistable object is dirty.
static Boolean	isFieldLoaded(Object obj, String memberName, javax.jdo.PersistenceManager pm)	Accessor for whether the specified member (field/property) of the passed persistable object is loaded.

Methods inherited from class java.lang.Object

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

Constructor Detail

DataNucleusHelperJDO

public DataNucleusHelperJDO()

Method Detail

getQueryResultCache

public static JDOQueryCache getQueryResultCache(javax.jdo.PersistenceManagerFactory pmf)

Convenience accessor for the query results cache.

Parameters:

pmf - The PMF

Returns:

The Query results cache

getFieldsInFetchPlanForClass

public static int[] getFieldsInFetchPlanForClass(javax.jdo.PersistenceManager pm,
                                                 String className)

Convenience accessor for the fields of a specified class that are currently in the FetchPlan.

Parameters:

pm - Persistence Manager

className - Name of the class

Returns:

The fields that are in the FetchPlan

getSingleFieldIdentityForDataNucleusIdentity

public static javax.jdo.identity.SingleFieldIdentity getSingleFieldIdentityForDataNucleusIdentity(org.datanucleus.identity.SingleFieldId dnid,
                                                                                                  Class targetClass)

Method to convert a DataNucleus "identity" for a single-field application id type to the JDO provided SingleFieldIdentity type. TODO The targetClass "name" is part of the dnid, so could minimise the input args possibly

Parameters:

dnid - DataNucleus identity

targetClass - The target class

Returns:

The JDO SingleFieldIdentity

getDataNucleusIdentityForSingleFieldIdentity

public static org.datanucleus.identity.SingleFieldId getDataNucleusIdentityForSingleFieldIdentity(javax.jdo.identity.SingleFieldIdentity sfid)

getObjectIdClassForInputIdClass

public static String getObjectIdClassForInputIdClass(String objectIdClass)

getMetaDataForClass

public static org.datanucleus.metadata.ClassMetaData getMetaDataForClass(javax.jdo.PersistenceManagerFactory pmf,
                                                                         Class cls)

Accessor for the MetaData for the specified class

Parameters:

pmf - PersistenceManager factory

cls - The class

Returns:

The MetaData for the class

getClassesWithMetaData

public static String[] getClassesWithMetaData(javax.jdo.PersistenceManagerFactory pmf)

Accessor for the names of the classes that have MetaData for this PMF.

Parameters:

pmf - The PMF

Returns:

The class names

getDetachedStateForObject

public static Object[] getDetachedStateForObject(Object obj)

Accessor for the jdoDetachedState field of a detached object. The returned array is made up of :

• 0 - the identity of the object
• 1 - the version of the object (upon detach)
• 2 - loadedFields BitSet
• 3 - dirtyFields BitSet

Parameters:

obj - The detached object

Returns:

The detached state

getDirtyFields

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

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

Parameters:

obj - The persistable object

pm - The Persistence Manager (only required if the object is detached)

Returns:

Names of the dirty fields

getLoadedFields

public static String[] getLoadedFields(Object obj,
                                       javax.jdo.PersistenceManager pm)

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

Parameters:

obj - Persistable object

pm - The Persistence Manager (only required if the object is detached)

Returns:

Names of the loaded fields

isFieldLoaded

public static Boolean isFieldLoaded(Object obj,
                                    String memberName,
                                    javax.jdo.PersistenceManager pm)

Accessor for whether the specified member (field/property) of the passed persistable object is loaded.

Parameters:

obj - The persistable object

memberName - Name of the field/property

pm - PersistenceManager (if the object is detached)

Returns:

Whether the member is loaded

isFieldDirty

public static Boolean isFieldDirty(Object obj,
                                   String memberName,
                                   javax.jdo.PersistenceManager pm)

Accessor for whether the specified member (field/property) of the passed persistable object is dirty.

Parameters:

obj - The persistable object

memberName - Name of the field/property

pm - PersistenceManager (if the object is detached)

Returns:

Whether the member is dirty