用Java实现为某公司编写一个工资支付系统,用于计算某一类员工的月薪。该公司共有四类员工:领固定月薪的(SalariedEmployee);计时取酬的(HourlyEmployee,如果一月工时超过160小时,则还需对额外的工时支付加班

费);销售提成员工(SalesEmployee,除了固定月薪外,还有销售提成);经理(Manager,除了固定月薪外,还有奖金)。以下是Java实现代码：

abstract class Employee {
    private String name;
    private int age;
    private String department;

    public Employee(String name, int age, String department) {
        this.name = name;
        this.age = age;
        this.department = department;
    }

    public abstract double getSalary();
}

class SalariedEmployee extends Employee {
    private double monthlySalary;

    public SalariedEmployee(String name, int age, String department, double monthlySalary) {
        super(name, age, department);
        this.monthlySalary = monthlySalary;
    }

    public double getSalary() {
        return monthlySalary;
    }
}

class HourlyEmployee extends Employee {
    private double hourlyRate;
    private double hoursWorked;

    public HourlyEmployee(String name, int age, String department, double hourlyRate, double hoursWorked) {
        super(name, age, department);
        this.hourlyRate = hourlyRate;
        this.hoursWorked = hoursWorked;
    }

    public double getSalary() {
        if (hoursWorked <= 160) {
            return hourlyRate * hoursWorked;
        } else {
            return hourlyRate * 160 + hourlyRate * 1.5 * (hoursWorked - 160);
        }
    }
}

class SalesEmployee extends Employee {
    private double monthlySalary;
    private double commissionRate;
    private double salesAmount;

    public SalesEmployee(String name, int age, String department, double monthlySalary, double commissionRate, double salesAmount) {
        super(name, age, department);
        this.monthlySalary = monthlySalary;
        this.commissionRate = commissionRate;
        this.salesAmount = salesAmount;
    }

    public double getSalary() {
        return monthlySalary + commissionRate * salesAmount;
    }
}

class Manager extends Employee {
    private double monthlySalary;
    private double bonus;

    public Manager(String name, int age, String department, double monthlySalary, double bonus) {
        super(name, age, department);
        this.monthlySalary = monthlySalary;
        this.bonus = bonus;
    }

    public double getSalary() {
        return monthlySalary + bonus;
    }
}

在这个例子里，我们使用了抽象类来定义所有员工的通用属性和方法，然后通过继承来实现不同类型员工的特定属性和方法，最后通过调用各自的 `getSalary()` 方法来获得每个员工的月薪。