Hibernate version:2.17c

Hello,

I have a class User, with two sub-classes Doctor and Patient, I use Table Per Class Hierarchy mapping the class inheritance to the table User.
i.e, I have used a discriminator (column UserType).

My question is, when I retrieve a User instance from User table, how can I know the User is a a Doctor or Patient, that is, how can I get the discriminator value? (Hibernate will automatically set and retrieve the discrimnator values < from hibernate in Action>).

Thanks a lot.

You use the instanceof operator.

Just a warning: Be careful of using the instanceof operator when you have provided a proxy for your objects.

The instanceof seems to work well with version 2.17 but fails with 3.0Beta1. Is this intended? And when, how to find out the subtype?
the debugger says:
the return object is of type <base-class>$$EnhancerByCGLIB$$...
This has two additional fields:
CGLIB$$BOUND=true
CGLI$$CALLBACK_0=CGLIBLazyInitializer
The CGLIBLazyInitializer in turn has a field target that is of type <sub-class>.
How can i get access to this information?

khs
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Thanks a lot. I will try.

Hello,

Actually I am still comfused with that.

Now class inheritance is like:

class User{};
class Doctor extends User{};
class Patient extends User{};

With "table per class hiberarchy" to map table User, with discriminator UserType

Now I retrieve User u = findByID() from table User, then can we use "instanceof" to get whether u is a Doctor or a Patient?

I doublt that, because (parent_instnace instanceof child_class), for exampe, (u instanceof Doctor) should create compile error, right?

Thanks for any help.

work fine for me

thanks croco

What about when a Doctor is also a Patient? How can you get away with having a row in each of your subclasses that share a single row in the parent class?