G.4. Relationship between Superclasses and Subclasses
We now use an inheritance hierarchy containing types of employees in a company’s payroll application to discuss the relationship between a superclass and its subclass. In this company, commission employees (who will be represented as objects of a superclass) are paid a percentage of their sales, while base-salaried commission employees (who will be represented as objects of a subclass) receive a base salary plus a percentage of their sales.
We create an example that sets the
CommissionEmployee instance variables to
private to enforce good software engineering. Then we show how the
BasePlusCommissionEmployee subclass can use
public methods to manipulate (in a controlled ...