34、超类与子类的关系及继承实现

超类与子类的关系及继承实现

1. 创建和使用 BasePlusCommissionEmployee 类

BasePlusCommissionEmployee 类代表了一种除了佣金之外还能获得基本工资的员工。该类包含了员工的名、姓、社保号码、总销售额、佣金率和基本工资等信息。

以下是 BasePlusCommissionEmployee 类的代码：

// Fig. 9.6: BasePlusCommissionEmployee.java
// BasePlusCommissionEmployee class represents an employee who receives
// a base salary in addition to commission.
public class BasePlusCommissionEmployee {
    private final String firstName;
    private final String lastName;
    private final String socialSecurityNumber;
    private double grossSales; // gross weekly sales
    private double commissionRate; // commission percentage
    private double baseSalary; // base salary per week

    // six-argument constructor
    public BasePlusCommiss