Module org.datanucleus.api.jpa
Package org.datanucleus.api.jpa

Class NucleusJPAHelper

  • public class NucleusJPAHelper
extends Object
    Helper for persistence operations with JPA.

    • Constructor Detail

      • NucleusJPAHelper

        public NucleusJPAHelper()

    • Method Detail

      • getSurrogateVersionForEntity

        public static Object getSurrogateVersionForEntity​(Object obj)
        Convenience method to allow access to the version of an object when it is using DN Extension "surrogate-version".
        Parameters:
        obj - The entity object
        Returns:
        The (surrogate) version

      • getDatastoreIdForEntity

        public static Object getDatastoreIdForEntity​(Object obj)
        Convenience method to allow access to the datastore id of an object when it is using DN Extension "datastore-id".
        Parameters:
        obj - The entity object
        Returns:
        The datastore id key

      • getObjectId

        public static Object getObjectId​(Object obj)

      • 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

      • 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.persistence.EntityManager 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

      • 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