[FIXED] Using javax @Transient annotation with a field of MappedSuperclass

Issue

Javax's @Transient annotation when applied over an @Entity class' field will prevent the annotated field from being persisted into the database as a column. Is there a method to selectively achieve this behavior (of excluding the persistence of a certain column) for a field in a MappedSuperclass? To clarify, I want some field x present in a MappedSuperclass to be persisted for some entity classes that extend the MappedSuperclass and excluded from persistence in some other extending entity classes.

I have tried shadowing the field x in the extending class and annotating it with @Transient, however, this doesn't seem to work. Is there any alternative approach that would enable this behavior?

Solution

Yes. In the children entity class that extends @MappedSuperclass , you can configure it to use the property access for this transient field .

So assuming a given @MappedSuperclass has a @Transient field :

@MappedSuperclass
public abstract class Parent {

    @Transient
    protected LocalDateTime createdTs;

}

For the children entity that want to include this transient field , you could do :

@Entity
@Table(name = "foo")
public class Foo extends Parent {

   @Id
   private Long id;


   @Access(AccessType.PROPERTY)
   @Column(name= "createTs")
   public LocalDateTime getCreatedTs() {
        return this.createdTs;
    }

}

And for the children entity that want to exclude this transient field , you could do :

@Entity
@Table(name = "foo")
public class Foo extends Parent {

   @Id
   private Long id;

}

Answered By - Ken Chan
Answer Checked By - Terry (JavaFixing Volunteer)