Android™ How to Program, Second Edition

G.12.5. Modifying Class SalariedEmployee for Use in the Payable Hierarchy

Figure G.26 contains a modified SalariedEmployee class that extends Employee and fulfills superclass Employee’s contract to implement Payable method getPaymentAmount. This version of SalariedEmployee is identical to that of Fig. G.17, but it replaces method earnings with method getPaymentAmount (lines 34–38). Recall that the Payable version of the method has a more general name to be applicable to possibly disparate classes. The remaining Employee subclasses (e.g., HourlyEmployee, CommissionEmployee and BasePlusCommissionEmployee) also must be modified to contain method getPaymentAmount in place of earnings to reflect the fact that Employee now implements Payable. We leave ...