Hibernate inheritance JOINED + TABLE PER CLASS

Question

I have this strange hierarchy:

Class A is abstract (but it is an entity)
Class B (abstract) and C both extend class A (TABLE_PER_CLASS).
Class B is also extended by classes D and E but this time it is JOINED.

I want the ID of the A class to be the ID of all others.

Can this be done?

I get strange errors of IDs. can any one show me how to map?

This is how I did it:

@Entity
@Inheritance(strategy = InheritanceType.TABLE_PER_CLASS)
public abstract class A {
      @Id
        @GeneratedValue(strategy = GenerationType.TABLE)
    protected Integer id;
}

Class C:

@Entity
@Table(name = "managers")
public class C extends A {

Class B:

@Entity
@Table(name = "bb")
@Inheritance(strategy = InheritanceType.JOINED)
@DiscriminatorColumn(name = "discriminator", discriminatorType = DiscriminatorType.STRING)
public abstract class B extends A {

Class C,D:

@Entity
@Table(name = "cc"/"dd")
@DiscriminatorValue("CC"/"DD")
public class C (or D) extends B {

Have you looked at [Mixing Joined and Table per concrete class inheritance](http://stackoverflow.com/questions/5977717/mixing-joined-and-table-per-concrete-class-inheritance)? — Greg Kopff, Mar 31 '14 at 11:41

score 1 · Accepted Answer · edited May 23 '17 at 12:05

1

While mixing inheritance strategies in an inheritance tree can be sort of accomplished (https://stackoverflow.com/a/3916998/131929 refers to Java Persistence with Hibernate -> 5.1.5 Mixing inheritance strategies (p207-p210)) I, and everybody else I know, advise against it.

Sidenote, I suggest you always use @MappedSuperclass rather than @Entity for abstract classes.

edited May 23 '17 at 12:05

Community

1
1

answered Mar 31 '14 at 12:27

Marcel Stör

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Hibernate inheritance JOINED + TABLE PER CLASS

1 Answers1