How to map Java generic instances with Hibernate

I'm trying to map Generic types in Hibernate. I've searched and couldn't find clear answers how to do it. Help will be much appreciated. Here are some example classes:

public class Person {
  ...
}

public class PersonA extends Person {
  ...
}
public class PersonB extends Person {
  ...
}
public class PersonHolder<P extends Person> {
  private P person;
  ...
}
public class People {
  private Map<String, PersonHolder<PersonA> > aPeople;
  private Map<String, PersonHold开发者_StackOverflow中文版er<PersonB> > bPeople;
  ...
}

I'm using native Hibernate mapping (XML, no annotations). I already have Hibernate mapping for Person, PersonA and PersonB, but I would like to know if it's possible to map class PersonHolder's instantiation in a generic way without explicitly create generic-implementing sub-classes such as:

public class PersonAHolder extends PersonHolder<PersonA> {
  ...
}

(and mapping this class as an ordinary class).

Thanks!

AFAIK that is unfortunately not possible. In bytecode there's no difference between PersonHolder<PersonA> and PersonHolder<PersonB> due to type erasure and thus Hibernate would not be able to distinguish between them.

Edit: to clarify, I'm talking about direct instances of PersonHolder. If you have subclasses that define a concrete generic type, you can get the generic type information. But that would require to have subclasses, which contradicts the question:

I would like to know if it's possible to map class PersonHolder's instantiation in a generic way without explicitly create generic-implementing sub-classes such as: