OneToOne relationship - Provided id of the wrong type

earth82 · **Posted:** Fri Aug 28, 2009 9:18 am

Hi to all!

Sorry for the newbie question, but I have a problem with a OneToOne relationship.

I have this situation in a legacy DB that i can't modify:
A
(fieldOne, fieldTwo, x) PK
foo

B
(fieldOne, foo, y) PK

The OneToOne relationship that I have to implement is on:
A.foo=B.foo

The java code is:

Code:

@Entity
@Table(name = "A")
public class A implements java.io.Serializable {
    private AId id; // it contains 'fieldOne', 'fieldTwo' and 'x'
    private int foo;

    private B b; // 1-to-1 relationship with B

    // .. code ..

    @OneToOne(mappedBy="a", targetEntity=B.class)
    public B getB(){ ... }

    public void setB(B b){ ... }

Code:

@Entity
@Table(name = "B", uniqueConstraints = @UniqueConstraint(columnNames = "ID"))
public class Bimplements java.io.Serializable {
    private B BId; // it contains 'fieldOne', 'foo' and 'y'.
    private A a;   // 1-to-1 relationship with A


    // .. code ..

    @OneToOne(targetEntity=A.class)
    @JoinColumn(name="FOO") // the name of the property foo in the table A.
    public Ress getA() { ... }

    public void setA(A a){ ... }

But this implementation raises:
Exception in thread "main" org.hibernate.TypeMismatchException: Provided id of the wrong type. Expected: class db.AId, got db.BId

And .. I simply don't understand why!

Thanks a lot!