Hibernate version:3

I tried to add a version property to my base class using the javax.persistence.Version annotation:

public abstract class BaseManagedObject implements Serializable
{

@Version
@Column(name="revision" )
protected Long revision;

/**
* Get the Hibernate version for this managed object
* @return the object's version
*/
public Long getRevision()
{
return revision;
}


But when I updated an object that extends this base class, the version field was never updated.
However, when I moved this property into the extended class, the version field got updated as expected:

@Entity
@GeneratedEntity
@Table(name = "User_Table")
public class User extends BaseManagedObject
{
@Version
@Column(name="revision" )
private Long revision;

/**
* Get the Hibernate version for this managed object
* @return the object's version
*/
public Long getRevision()
{
return revision;
}


I did not annotate the base class with @Entity, since I did not want to create a table for it. In fact, when I added @Entity and @Table annotations, I got AnnotationException from the SessionFactory at startup.

Thanks for any help

Hi ped,

indeed you need not to annotate your base class as Entity, but just do this

Thanks for the reply Carlo -
I replaced the @Entity annotation with @MappedSuperclass, but I got the same result - the version field is not intialized at create time or updated when the object is updated.

Hi ped,

maybe the problem is due to the fact that you have a duplicate version attribute - in the base class and in the derived class. Remove it from the derived class.

Here's a very simple tutorial that demonstrates how to map inheritance with Hibernate3 and JPA annotations. It's very simple, and it might give you a good idea on where to add the appropriate annotations:

http://jpa.ezhibernate.com/Javacode/learn.jsp?tutorial=16mappinginheritancewithjpa

I never ran with the version attribute defined in both classes. I was trying to show how I defined and annotated the attribute in each class, when it was declared in the class.

Thanks,

I discovered the problem - tho I don't think this should be an issue...

When I place the @Version and @Column annotation to the field declaration in my base class, the extended class has its version column updated correctly.
When I place the annotations on the getter method for the version column in the base class, the extended class does NOT get its version column updated.

I believe that @Version is valid for both methods and for fields. It seems to only work for the field in this case.

Thanks for the help,

actually it's your @Id annotation that determines if it looks only at field level annotation or only at getter level annotations