Example: Concrete class as a mapped superclass

[MappedSuperclass]
public class Employee {

    [Id] protected Integer empId;
    [Version] protected Integer version;
    [ManyToOne] [JoinColumn(name="ADDR")]
    protected Address address;

    public Integer getEmpId() { ... }
    public void setEmpId(Integer id) { ... }
    public Address getAddress() { ... }
    public void setAddress(Address addr) { ... }
}

// Default table is FTEMPLOYEE table
[Entity]
public class FTEmployee extends Employee {

    // Inherited empId field mapped to FTEMPLOYEE.EMPID
    // Inherited version field mapped to FTEMPLOYEE.VERSION
    // Inherited address field mapped to FTEMPLOYEE.ADDR fk

    // Defaults to FTEMPLOYEE.SALARY
    protected Integer salary;

    public FTEmployee() {}

    public Integer getSalary() { ... }

    public void setSalary(Integer salary) { ... }
}

[Entity] [Table(name="PT_EMP")]
[AssociationOverride(Name="address")]
[JoinColumn(AttributeRef="address",Name="ADDR_ID")]
public class PartTimeEmployee extends Employee {

    // Inherited empId field mapped to PT_EMP.EMPID
    // Inherited version field mapped to PT_EMP.VERSION
    // address field mapping overridden to PT_EMP.ADDR_ID fk
    [Column(name="WAGE")]
    protected Float hourlyWage;

    public PartTimeEmployee() {}

    public Float getHourlyWage() { ... }
    public void setHourlyWage(Float wage) { ... }
}