NPE with forRevisionsOfEntity query on an entity with a @ManyToOne relation

[kru.sh]

Hi

I have 2 entities Limits and UserGroup where Limits is audited and UserGroup is not. They are audited ad follows-

Entity Limits-

@Entity

@Table(name = "LMT")

public final class LMT {

    @ManyToOne

    @JoinColumn(name = "OWNER_GROUP_ID", referencedColumnName = "ID")

    @Audited(targetAuditMode = RelationTargetAuditMode.NOT_AUDITED)

    private UserGroup ownerGroup;

...

}

Entity UserGroup-

@Entity

@Table(name = "ENT_USER_GROUPS")

public final class UserGroup

{

OneToMany and ManyToMany relations with other entities

attributes and methods

}

The problem i am facing is when querying for revisions of enitity Limits using forRevisionsOfEntity-

AuditQuery query3 = reader.createQuery().forRevisionsOfEntity(Limits.class, true, false).add(AuditEntity.id().eq(2186));

                      System.out.println("results3 -------- "  + " " +  query3.getResultList());

This gives a NPE as follows-

java.lang.NullPointerException

          at org.hibernate.tuple.entity.AbstractEntityTuplizer.createProxy(AbstractEntityTuplizer.java:755)

          at org.hibernate.persister.entity.AbstractEntityPersister.createProxy(AbstractEntityPersister.java:4129)

          at org.hibernate.envers.entities.mapper.relation.ToOneIdMapper.mapToEntityFromMap(ToOneIdMapper.java:101)

          at org.hibernate.envers.entities.mapper.MultiPropertyMapper.mapToEntityFromMap(MultiPropertyMapper.java:115)

          at org.hibernate.envers.entities.EntityInstantiator.createInstanceFromVersionsEntity(EntityInstantiator.java:99)

          at org.hibernate.envers.query.impl.RevisionsOfEntityQuery.list(RevisionsOfEntityQuery.java:134)

          at org.hibernate.envers.query.impl.AbstractAuditQuery.getResultList(AbstractAuditQuery.java:102)

          at com.LimitChangesTest.test_get_all_limit_changes(LimitChangesTest.java:124)

However, if comment out the @Audited(..) annotation for ownerGroup or put a @NoTAudited i.e on not auditing it, the query returns the revisions of entity Limits( with ownerGroup=null). I have used RelationTargetAuditMode.NOT_AUDITED for ownerGroup  as the entity is not audited. So i am guessing the annotations are right, but i can't figure out why auditing this property is causing a NPE.

Thanks.

[kru.sh]

Found the solution-

removing final keyword from the UserGroup class solves the issue. refer https://community.jboss.org/thread/197147

Thanks.