CODEWITHSUNDEEP
javahibernatesubclass
Andrea
Andrea

Reputation: 724

Force Hibernate to return the correct subclass proxy

I have the following Hibernate classes:

@Entity
@Inheritance(strategy = InheritanceType.SINGLE_TABLE)
public abstract class User {
    @Id
    private Long id;
}

@Entity
public class Patient extends User {
    /* ... */
}

@Entity
public class Doctor extends User {
    /* ... */
}

During the login phase, I execute

User user = db.createQuery("from User where email = :email")
              .setParameter("email", email)
              .uniqueResult();

Unluckily, user is always a proxy of User, so I can't cast it to Doctor. Can I force Hibernate to look closely at the user type and return the right proxy, possibly without executing another query?

Upvotes: 3

Views: 838

Answers (1)

JB Nizet
JB Nizet

Reputation: 691765

I think it should return the right subclass instance if this user is not yet loaded as a User (due to a previously loaded association, for example).

If not, then you have no way of letting it return an actual Doctor instance. So you should either call a polymorphic method of User, or using proprietary Hibernate code to check if it's a proxy, initialize it and get the wrapped object.

If you know in advance that it's a Doctor, then use "from Doctor" rather than "from User".

Upvotes: 1

Related Questions