第十二周上机练习

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。

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。
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。
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。
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。
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。

3、利用接口实现动态的创建对象:(知识点:接口 )
(1)创建4个类
1苹果
2香蕉
3葡萄
4园丁
(2)在三种水果的构造方法中打印一句话.
以苹果类为例
class apple
{
    public apple()
    {
        System.out.println(“创建了一个苹果类的对象”);
}
}
(3)类图如下:

(4)要求从控制台输入一个字符串,根据字符串的值来判断创建三种水果中哪个类的对象。
运行结果如图:

package itheima01.com; 
public  abstract class Shape {
    double area;
    double per;
    String color;
 
 
 
    public Shape(){
 
    }
 
    public Shape(String color){
        this.color = color;
    }
 
    public abstract double getArea();
    public abstract double getPer();
    public abstract void showAll();
 
    public String getColor(){
        return this.color;
    }
}
package itheima01.com;
 
public class Rectangle extends Shape{
    int weidth;
    int height;
      
    public Rectangle() {
      
    }
      
    public Rectangle(int weidth,int height,String color){
        super(color);
        this.weidth = weidth;
        this.height = height;
    }
      
      
     public double getArea() {
        this.area = weidth * height; 
        return this.area;
     }
      
    public double getPer() {
        this.per = 2 * (weidth + height);
        return this.per;
    }
      
    public void showAll() {
        System.out.println("该矩形长为"+this.weidth+",宽为"+this.height+",周长为"+this.getPer()+",面积为"+this.getArea()+",颜色为"+this.getColor());
      
            }
      
    }
 
package itheima01.com;
 
public class Circle extends Shape {
     double radius;
        double pi = Math.PI;
      
        public Circle(){
      
        }
        public Circle(double radius,String color){
                super(color);
                this.radius = radius;
            }
      
        public double getArea() {
              double area =pi * radius *radius;
            return area;
        }
      
        public double getPer() {
            double per = 2 * pi * radius;
            return per;
        }
      
        public void showAll() {
            System.out.println("半径为"+this.radius+"的圆,周长为"+this.getPer()+",面积为"+this.getArea()+",颜色为"+this.getColor());
      
        }
    }
package itheima01.com;
 
public class PolyDemo {
    public static void main(String[] args) {
        Rectangle r = new Rectangle(8,9,"brown");
        Circle c = new Circle(10,"pink");
        r.showAll();
        c.showAll();
    }
}
2.package itheima01.com;

public class ColaEmployee {
    String name;
    int month;
 
    public ColaEmployee() {
 
    }
 
    public ColaEmployee(String name, int month) {
        this.name = name;
        this.month = month;
    }
 
    public double getSalary(int month) {
        return 0;
    }
 
}package itheima01.com;

public class SalariedEmployee extends  ColaEmployee {
    double monSalary;
     
    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 itheima01.com;

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 itheima01.com;

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 itheima01.com;

public class TestCompany {
    public static void main(String[] args) {
        
        ColaEmployee[] z = {
                new SalariedEmployee("员工: 王二麻子", 5, 12300),
                new HourlyEmployee("员工: 张三", 9, 140, 360),
                new SalesEmployee("员工 :李四", 7, 873200, 0.25)
                };
        for (int i = 0; i <z.length; i++) {
            new Company().getSalary(z[i],8);
        }
    }
}package itheima01.com;

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

3.package itheima01.com;

public interface Fruit {
void apple();
void banana();
void orange();


}
package itheima01.com;

public class apple  implements Fruit{
    public void apple(){
        System.out.println("创建了一个苹果类的对象");
    }

    @Override
    public void banana(){
        
    }
    @Override
public void orange(){
        
    }
}
package itheima01.com;

public class banana implements Fruit {
public void banana(){
    System.out.println("创建了一个香蕉类的对象");
}
@Override
public apple(){
}
@Override
public orange(){
}
}
package itheima01.com;
import java.util.*;
public class Text {
public static void main(String[]args){
    Fruit b=new banana();
    Scanner input=new Scanner (System.in);
    System.out.println("请输入您要创建的类:");
    String attr=input.nextLine();
    if (attr.equals("banana")){
        Fruit fruit =new banana();
        fruit.banana();
    }
    
    else if (attr.equals("orange")){
        Fruit fruit =new orange();
        fruit.orange();
    
    }
    else if (attr.equals("apple")){
        Fruit fruit =new apple();
        fruit.apple();
    
    }
    else System.out.println("输入有误");
}
}
package itheima01.com;
public class orange implements Fruit {
        public void orange(){
            System.out.println("创建了一个橙子的对象");
        }
        @Override
        public void apple(){
            
        }
        @Override
    public void banana(){
        
    }
    }

原文地址:https://www.cnblogs.com/1774ax/p/12929542.html