1、设计四个类,分别是:(知识点:抽象类及抽象方法)

(1)Shape表示图形类,有面积属性area、周长属性per,颜色属性color,有两个构造方法(一个是默认的、一个是为颜色赋值的),还有3个抽象方法,分别是:getArea计算面积、getPer计算周长、showAll输出所有信息,还有一个求颜色的方法getColor。

(2)2个子类:

1)Rectangle表示矩形类,增加两个属性,Width表示长度、height表示宽度,重写getPer、getArea和showAll三个方法,另外又增加一个构造方法(一个是默认的、一个是为高度、宽度、颜色赋值的)。

2)Circle表示圆类,增加1个属性,radius表示半径,重写getPer、getArea和showAll三个方法,另外又增加两个构造方法(为半径、颜色赋值的)。

 (3)一个测试类PolyDemo,在main方法中,声明创建每个子类的对象,并调用2个子类的showAll方法。

package hsy;

public abstract class Shape {
    protected double area;
    protected double per;
    protected String color;

    public Shape() {

    }

    public Shape(String color) {
        this.color = color;
    }

    public abstract void getArea();

    public abstract void getPer();

    public abstract void showAll();

}

  

package hsy;

public class Rectangle extends Shape {
    double width;
    double height;

    public Rectangle() {

    }

    public Rectangle(double width, double height, String color) {
        super();
        this.width = width;
        this.height = height;
        this.color = color;
    }

    @Override
    public void getArea() {
        area = width * height;

    }

    @Override
    public void getPer() {
        per = (width + height) * 2;
    }

    @Override
    public void showAll() {
        System.out.println("矩形面积为:" + area + ",周长为:" + per + ",颜色:" + color);
    }

}

  

package hsy;
public class Circle extends Shape {
    double radius;

    public Circle() {

    }

    public Circle(double radius, String color) {
        this.color = color;
        this.radius = radius;
    }

    @Override
    public void getArea() {
        area = radius * radius * 3.14;
    }

    @Override
    public void getPer() {
        per = 2 * radius * 3.14;
    }

    @Override
    public void showAll() {
        System.out.println("圆的面积为:" + area + ",周长为:" + per + ",颜色:" + color);
    }
}

  

package hsy;

public class PolyDemo {
    public static void main(String[] args) {
        Circle circle = new Circle(3, "break");
        Rectangle rectangle = new Rectangle(2, 4, "red");
        circle.getArea();
        circle.getPer();
        circle.showAll();

        rectangle.getArea();
        rectangle.getPer();
        rectangle.showAll();

    }
}

  

2、Cola公司的雇员分为以下若干类:(知识点:多态)

(1) ColaEmployee :这是所有员工总的父类,属性:员工的姓名,员工的生日月份。

Ÿ   方法:getSalary(int month) 根据参数月份来确定工资,如果该月员工过生日,则公司会额外奖励100 元。

(2) SalariedEmployee :     ColaEmployee 的子类,拿固定工资的员工。

Ÿ   属性:月薪

(3) HourlyEmployee :ColaEmployee 的子类,按小时拿工资的员工,每月工作超出160 小时的部分按照1.5 倍工资发放。

Ÿ   属性:每小时的工资、每月工作的小时数

(4) SalesEmployee :ColaEmployee 的子类,销售人员,工资由月销售额和提成率决定。

Ÿ   属性:月销售额、提成率

(5) 定义一个类Company,在该类中写一个方法,调用该方法可以打印出某月某个员工的工资数额,写一个测试类TestCompany,在main方法,把若干各种类型的员工放在一个ColaEmployee 数组里,并单元出数组中每个员工当月的工资。

 
package hsy;

public class ColaEmployee {
    String name;
    int month;

    public ColaEmployee() {

    }

    public ColaEmployee(String name, int month) {
        super();
        this.name = name;
        this.month = month;
    }

    public double getSalary(int month) {
        return 0;
    }

}

  

package hsy;

public class SalariedEmployee extends ColaEmployee {
    double monSalary;

    public SalariedEmployee() {
        super();
        // TODO Auto-generated constructor stub
    }

    public SalariedEmployee(String name, int month, double monSalary) {
        super(name, month);
        this.monSalary = monSalary;
    }

    public double getSalary(int month) {
        if (super.month == month) {
            return monSalary + 100;
        } else {
            return monSalary;
        }
    }

}

  

package hsy;

public class HourlyEmployee extends ColaEmployee {
    private int hourSalary;
    private int hourNum;

    public HourlyEmployee(String name, int month, int hourSalary, int hourNum) {
        super(name, month);
        this.hourSalary = hourSalary;
        this.hourNum = hourNum;

    }

    public double getSalary(int month) {
        if (super.month == month) {
            if (hourNum > 160) {
                return hourSalary * 160 + hourSalary * (hourNum - 160) * 1.5 + 100;
            } else {
                return hourSalary * hourNum + 100;
            }
        } else {
            if (hourNum > 160) {
                return hourSalary * 160 + hourSalary * (hourNum - 160) * 1.5;
            } else {
                return hourSalary * hourNum;
            }
        }

    }

}

  

package hsy;

public class SalesEmployee extends ColaEmployee {
    private int monthSales;
    private double royaltyRate;

    public SalesEmployee(String name, int month, int monthSales, double royaltyRate) {
        super(name, month);
        this.monthSales = monthSales;
        this.royaltyRate = royaltyRate;
    }

    public double getSalary(int month) {
        if (super.month == month) {
            return monthSales * royaltyRate + 100;
        } else {
            return monthSales * royaltyRate;
        }
    }

}

  

package hsy;

public class Company {
    public void getSalary(ColaEmployee c, int month) {
        System.out.println(c.name + "在" + month + "月的月薪为" + c.getSalary(month) + "元");
    }

}

  

package hsy;

public class Text {
    public static void main(String[] args) {
        // TODO Auto-generated method stub

        // 创建、初始化数组
        ColaEmployee[] cel = { new SalariedEmployee("salariedEmployee", 6, 25000), // name,month,月薪
                new HourlyEmployee("hourlyEmployee", 5, 200, 200), // name,month,时薪,小时数
                new SalesEmployee("salesEmployee", 3, 60000, 0.3)// name,month,月销售额,提成率
        };
        // 数组遍历
        for (int i = 0; i < cel.length; i++) {
            new Company().getSalary(cel[i], 7);
        }
    }

}