Changing cats into dogs

Hibernate Modifying subclass's discriminator value on update

Well, despite the naysayers above I've succeeded in doing the unnatural and have changed the type of a polymorphic Hibernate class.

Dog changeCatToDog(Cat cat){
   int res = (Integer) getHibernateTemplate().execute(new HibernateCallback(){
 public Object doInHibernate(Session sess) throws Exception {
 String hqlUpdate = "update Animal set discriminator = 'dog' where animal_id = :id";
        int updatedEntities = sess.createQuery( hqlUpdate )
          .setLong( "id", cat.getId() )                            
   .executeUpdate();   
   return updatedEntities;   
  }});

    getHibernateTemplate().evict(t);

    return (Dog) getHibernateTemplate().get(Dog.class, cat.getId());
}