Hibernate JPA ManyToOne composite key

Question

I'm trying to setup my entity to allow to pks. My database consist of two fields,

dealer_detail_id pk user_detail_id pk

Both join on id in corresponding tables.

I've tried this thus far without success.

@Embeddable
public class DealerUserPk implements Serializable {

    private Integer dealerDetail;
    private Integer userDetail;

DealerUser

@Embeddable
@Table(name = "dealer_user", schema = "account") 
public class DealerUser implements Serializable {

    @EmbeddedId
    private DealerUserPk id;

    @Id
    @ManyToOne
    @JoinColumn(name = "dealer_detail_id", referencedColumnName = "id")
    private DealerDetail dealerDetail;

    @Id
    @ManyToOne
    @JoinColumn(name = "user_detail_id", referencedColumnName = "id")
    private UserDetail userDetail;

DealerDetail

@Entity
@Table(name = "dealer_detail", schema = "account") 
public class DealerDetail implements Serializable {

    @Id
    private Integer id;

UserDetail

@Entity
@Table(name = "user_detail", schema = "account") 
public class UserDetail implements Serializable {

    @Id
    private Integer id;

Can anybody spot what I'm doing wrong?

Answer 1

This is correct:

@Embeddable
public class DealerUserPk implements Serializable {

    private Integer dealerDetail;
    private Integer userDetail;

1. But your DealerUser is annotated with embeddable it should be @Entity as you are using @Table annotation.

2. Need to add MapsId as it follows

    @Entity
    @Table(name = "dealer_user", schema = "account") 
     public class DealerUser implements Serializable {
   
   @EmbeddedId
   private DealerUserPk id;
   
   @MapsId("dealerDetail")
   @ManyToOne
   @JoinColumn(name = "dealer_detail_id", referencedColumnName = "id")
   private DealerDetail dealerDetail;
   
   @Id
   @MapsId("userDetail")
   @JoinColumn(name = "user_detail_id", referencedColumnName = "id")
   private UserDetail userDetail;
   

Try with that.