@MappedSuperclass
    public class Employee {
 
        @Id protected Integer id;
        @Version protected Integer version;
        @ManyToOne protected Address address;
        @OneToOne protected Locker locker;
 
        public Integer getId() { ... }
        public void setId(Integer id) { ... }
        public Address getAddress() { ... }
        public void setAddress(Address address) { ... }
        public Locker getLocker() { ... }
        public void setLocker(Locker locker) { ... }
        ...
    }
 
    @Entity
    @AssociationOverrides({
        @AssociationOverride(
                   name="address", 
                   joinColumns=@JoinColumn("ADDR_ID")),
        @AttributeOverride(
                   name="locker", 
                   joinColumns=@JoinColumn("LCKR_ID"))
        })
    public PartTimeEmployee { ... }