About null

issue

unexpected exception - in query

I received the following exception while trying to process a query:... com.objectdb.o.InternalException: null com.objectdb.o.InternalException at ...

 
api-jpa

javax.persistence.FetchType

Defines strategies for fetching data from the database.(Enum of JPA)

 
api-jpa

valueOf(name)

Returns the enum constant of this type with the specified name.(Static Method of javax.persistence.spi.LoadState)

 
api-jpa

valueOf(name)

Returns the enum constant of this type with the specified name.(Static Method of javax.persistence.AccessType)

 
api-jpa

javax.persistence.criteria.JoinType

Defines the three types of joins.(Enum of JPA)

 
api-jdo

javax.jdo.annotations.SequenceStrategy

Enumeration of the sequence strategy values.(Enum of JDO)

 
api-jdo

isTransactional(pc)

Tests whether the parameter instance is transactional.(Method of javax.jdo.spi.StateInterrogation)

 
api-jdo

valueOf(name)

Returns the enum constant of this type with the specified name.(Static Method of javax.jdo.annotations.InheritanceStrategy)

 
api-jpa

valueOf(name)

Returns the enum constant of this type with the specified name.(Static Method of javax.persistence.metamodel.Bindable.BindableType)

 
forum_thread

@MappedSuperclass and @Transient not working as I expected

The problem could be my expectation, since I'm fairly inexperienced with JPA.  But here is the problem: The base class of my entity hierarchy is annotated as @MappedSuperclass, and one of its fields is annotated @Transient.  I expected that when I persist a subclass, no table would be created for the superclass, and the transient field would not appear in any table. The actual result is that there is a table for the superclass.  When I try to examine it in ObjectDB Explorer, it throws a NPE. ... named for the transient field.  All its values are null. Here is my base class: package krum. twj . db ; ...