Re: [eclipselink-users] @OptimisticLocking => NullPointerException

[Tom Ware <tom.ware@xxxxxxxxxx>]

Hi Michael,

  I see a potential bug in the code in 
CascadeLockingPolicy.initUnmappedFieldsQuery, but cannot quite reproduce the 
issue and hoping you can help me narrow it down.

  Assuming you are using only JPA annotations/xml to map your model, the issue 
appears to be related to a UnidirectionalOneToManyMapping (a OneToMany mapping 
without a backpointer).  Additionally, I expect that mapping should be 
@PrivateOwned, or orphanRemoval=true.

  In addition, you would likely see this where you are updating the target of a 
relationship to a new object in a chain of objects with cascaded locking.

  Anything you could do figure out which mapping you have that is causing the 
problem and tell me how it is configured would help me identify the issue.

-tom



On 02/07/2013 8:54 AM, Michael Hönnig wrote:
> Hi Tom,
>
> > What version of EclipseLink?
>
> 2.4.2.v20130315-93567e3
>
> > Please provide the full stack trace.
>
> java.lang.NullPointerException
>      at
> org.eclipse.persistence.internal.descriptors.CascadeLockingPolicy.initUnmappedFieldsQuery(CascadeLockingPolicy.java:241)
>
>      at
> org.eclipse.persistence.internal.descriptors.CascadeLockingPolicy.initUnmappedFields(CascadeLockingPolicy.java:216)
>
>      at
> org.eclipse.persistence.internal.descriptors.CascadeLockingPolicy.lockNotifyParent(CascadeLockingPolicy.java:272)
>
>      at
> org.eclipse.persistence.internal.descriptors.CascadeLockingPolicy.lockNotifyParent(CascadeLockingPolicy.java:324)
>
>      at
> org.eclipse.persistence.internal.sessions.UnitOfWorkImpl.calculateChanges(UnitOfWorkImpl.java:655)
>
>      at
> org.eclipse.persistence.internal.sessions.RepeatableWriteUnitOfWork.writeChanges(RepeatableWriteUnitOfWork.java:431)
>
>      at
> org.eclipse.persistence.internal.jpa.EntityManagerImpl.flush(EntityManagerImpl.java:798)
>
>      at
> com.sun.enterprise.container.common.impl.EntityManagerWrapper.flush(EntityManagerWrapper.java:418)
>
>
> > What object is involved, how is it mapped?
>
> The main entity class has these annotations:
>
> @Entity
> @Table(name = "CUSTOMER_AGREEMENT", uniqueConstraints =
> @UniqueConstraint(columnNames = "AGREEMENT_NO"))
> @Inheritance(strategy = InheritanceType.JOINED)
> @DiscriminatorColumn(name = "CONTRACT_TYPE", discriminatorType =
> DiscriminatorType.STRING, length = 1)
> @OptimisticLocking(cascade = true)
> public abstract class AgreementEntity ...
>
> But the whole entity structure is pretty complex.  I would need some hint on
> which parts to concentrte to extract it to reproduce the problem with a more
> simple structure.
>
> Best regards
> ... Michael
>
>
> > On 01/07/2013 12:22 PM, Michael Hönnig wrote:
> > > Dear EclipseLink community,
> > >
> > > We are getting a NullPointerExcption when using @OptimisticLocking.
> > >
> > > org.eclipse.persistence.internal.descriptors.CascadeLockingPolicy
> > > is the class where it happens:
> > >
> > > CascadeLockingPolicy.initUnmappedFieldsQuery(...) {
> > > ...
> > > SQLSelectStatement statement = new SQLSelectStatement();
> > > Iterator<DatabaseField> itUnmappedFields =
> > > m_unmappedQueryKeyFields.values().iterator();
> > > ...
> > > }
> > >
> > > called by
> > >
> > > CascadeLockingPolicy.initUnmappedFields(...) {
> > > ...
> > >   if(m_unmappedQueryKeyFields.isEmpty()) {
> > >                   m_unmappedQueryKeyFields = null;
> > >                   m_mappedQueryKeyFields = m_queryKeyFields;
> > >               }
> > >    initUnmappedFieldsQuery(uow);
> > > ...
> > > }
> > >
> > > Just 2 statements before initUnmappedFieldsQuery() is using
> > > m_unmappedQueryKeyFields, it is set to null.
> > >
> > > Is ths a bug or does anybody know which circumstances, e.g. annotations in our
> > > entities, could lead to this problem?`
> > >
> > > Best regards
> > > ... Michael
> > _______________________________________________
> > eclipselink-users mailing list
> > eclipselink-users@xxxxxxxxxxx
> > https://dev.eclipse.org/mailman/listinfo/eclipselink-users