Question

I have several Entity classes. Now I want to use @PostLoad in every entity. The function code is for every entity the same. So I made a super class (public abstract class AbstractModel {..}) which contain the @PostLoad method. Now is it possible to do this? In a quick test the method is not executed but the method is executed placed in the entity… Maybe someone has a workaround for this?

@MappedSuperclass
public class Parent implements Serializable
{

    @PostLoad
    public void postLoad()
    {
        System.out.println("postLoad called!");
    }


}

My entity class who extends from Parent:

@Entity
@Table(name = "albums") //de naam van de tabel wordt 'albums'
public class Album extends Parent implements Serializable
{
    private static final long serialVersionUID = 1L;

    @Id
    @GeneratedValue(strategy = GenerationType.AUTO)
    @Column(name = "id") //de naam van de kolom wordt 'id'
    private Long id;

...
}

And the error when I’m running it:

Exception [EclipseLink-30005] (Eclipse
Persistence Services –
2.0.2.v20100323-r6872): org.eclipse.persistence.exceptions.PersistenceUnitLoadingException
Exception Description: An exception
was thrown while searching for
persistence archives with ClassLoader:
sun.misc.Launcher$AppClassLoader@11b86e7

Internal Exception:
javax.persistence.PersistenceException:
Exception [EclipseLink-28018] (Eclipse
Persistence Services –
2.0.2.v20100323-r6872): org.eclipse.persistence.exceptions.EntityManagerSetupException

Exception Description: Predeployment
of PersistenceUnit [JPA_TestPU]
failed.

Internal Exception: Exception
[EclipseLink-7161] (Eclipse
Persistence Services –
2.0.2.v20100323-r6872): org.eclipse.persistence.exceptions.ValidationException
Exception Description: Entity class
[class jpatest.Album] has no primary
key specified. It should define either
an @Id, @EmbeddedId or an @IdClass. If
you have defined PK using any of these
annotations then make sure that you do
not have mixed access-type (both
fields and properties annotated) in
your entity class hierarchy.

Answer 1

At least “Java Persistence with JPA” says that this should work when applied to a mapped super class (mark AbstractModel with @MappedSuperClass).