See Thread at: http://www.techienuggets.com/Detail?tx=15288 Posted on behalf of a User Hi, did you resolve your issue? I have the same problem and am searching for a solution to solve it? Best Regards, Sascha In Response To: Hi, I'm having the following odd situation: | @Entity | @Inheritance(strategy = InheritanceType.JOINED) | public abstract class Customer { @Id private int id; } | | @Entity | public class SomeCustomer extends Customer { private String name; } | I'm using Entity Manager to retrieve entities by their primary key: | entityManager.find(Customer.class, 5); | The primary key 5 belongs to a SomeCustomer entity. It's in the id field of both Customer and SomeCustomer tables (due to join inheritance). However, the query returns an object that has the type Customer_$$_javassist_16 that cannot be cast to SomeCustomer (ClassCastException). However, if I execute the following query: | entityManager.find(SomeCustomer.class, 5); | I will see a warning in my logfile: ProxyWarnLog: Narrowing proxy to class SomeCustomer - this operation breaks == Subsequent call to the first find() query will now also return the right object of the right type. Does anybody know what's going on here or how I can manually narrow down my proxy object to what I want to have if it fails? Thanks a lot, Georges