java的第3次作业

1.编写一个Java应用程序,该程序包括3个类:Monkey类、People类和主类E。要求:

(1) Monkey类中有个构造方法:Monkey (String s),并且有个public void speak()方法,在speak方法中输出“咿咿呀呀......”的信息。
(2)People类是Monkey类的子类,在People类中重写方法speak(),在speak方法中输出“小样的,不错嘛!会说话了!”的信息。
(3)在People类中新增方法void think(),在think方法中输出“别说话!认真思考!”的信息。
(4)在主类E的main方法中创建Monkey与People类的对象类测试这2个类的功能。

 1 package LHB.inherit;
 2 import java.util.*;
 3 class Monkey 
 4 {   String s;
 5     public  Monkey(String s)
 6     {
 7         this.s=s;
 8     }
 9     public void speak()
10     {
11         System.out.println("好嗨哟!");
12     }
13 }
14 class People extends Monkey
15 {
16    public People(String s) {
17         super(s);
18     }
19 public void speak()
20    {
21        System.out.println("感觉人生已经到达了巅峰");
22    }
23    public void think()
24    {
25        System.out.println("你好牛哦,你才是真正的大人物");
26    }
27     
28 }
29 public class E 
30 {
31     public static void main(String[] args) 
32     { 
33         Scanner in=new Scanner(System.in);
34         String s;
35         s=in.next();
36         Monkey p=new Monkey(s);
37         People q=new People(s);
38        p.speak();
39        q.speak();
40        q.think();
41     }
42 
43 }

2.按要求编写一个Java应用程序:
(1)定义一个类,描述一个矩形,包含有长、宽两种属性,和计算面积方法。
(2)编写一个类,继承自矩形类,同时该类描述长方体,具有长、宽、高属性,和计算体积的方法。
(3)编写一个测试类,对以上两个类进行测试,创建一个长方体,定义其长、宽、高,输出其底面积和体积。

 1 package LHB.inherit;
 2 import java.util.*;
 3 class Rectangle
 4 {
 5     int length,width;
 6     public int area(int length,int width)/*矩形面积*/
 7     {
 8         this.length=length;
 9         this.width=width;
10         int s;
11         s=length*width;
12         return s;
13     }
14 }
15 class Cuboid extends Rectangle
16 {
17     int length,width,heigth;
18     public Cuboid(int length,int width,int heigth)
19     {
20         this.length=length;
21         this.width=width;
22         this.heigth=heigth;
23     }
24     public int area()/*长方体底面积*/
25     {
26         int s;
27         s=length*width;
28         return s;
29     }
30     public int Volume()/*长方体体积*/
31     {
32         int v;
33         v=area()*heigth;
34         return v;
35     }
36     
37 }
38 public class Test 
39 {
40 
41     public static void main(String[] args) 
42     {
43         int length,width,heigth;
44         Scanner in=new Scanner(System.in);
45         System.out.print("请输入长宽高:");
46         length=in.nextInt();
47         width=in.nextInt();
48         heigth=in.nextInt();
49         Rectangle p=new Rectangle();
50         Cuboid q=new Cuboid(length,width,heigth);
51         System.out.println("矩形的面积是:"+p.area(length, width));
52         System.out.println("长方体的体积是:"+q.Volume());
53 
54     }
55 
56 }

3.编写一个Java应用程序,设计一个汽车类Vehicle,包含的属性有车轮个数wheels和车重weight。小车类Car是Vehicle的子类,其中包含的属性有载人数loader。卡车类Truck是Car类的子类,其中包含的属性有载重量payload。每个类都有构造方法和输出相关数据的方法。最后,写一个测试类来测试这些类的功能。

 1 package LHB.inherit;
 2 import java.util.*;
 3 class Vehicle
 4 {
 5     int wheels,weight;/*车轮个数,车重*/
 6     public Vehicle(int wheels,int weight)
 7     {
 8         this.wheels=wheels;
 9         this.weight=weight;
10     }
11     public void print()
12     {
13         System.out.println("车轮个数是:"+wheels+"个\n"+"车重是:"+weight);
14     }
15 }
16 class Car extends Vehicle
17 {
18       int loader;/*车载人数*/
19     public Car(int wheels, int weight,int loader)
20     {    
21         super(wheels, weight);
22         this.loader=loader;
23     }
24     public void print()
25     {
26         System.out.println("车载人数是:"+loader);
27     }
28 }
29 class Truck extends Car
30 {
31     int payload;/*载重量*/
32     public Truck(int wheels, int weight, int loader,int payload) 
33     {
34         super(wheels, weight, loader);
35         this.payload=payload;
36     }
37     public void print()
38     {
39         System.out.println("载重量是:"+payload);
40     }
41 }
42 public class Testcar 
43 {
44 
45     public static void main(String[] args)
46     {
47         Scanner in=new Scanner(System.in);
48         int wheels,weight,loader,payload;
49         System.out.print("请输入车轮个数,车重,车载人数,载重量:");
50         wheels=in.nextInt();
51         weight=in.nextInt();
52         loader=in.nextInt();
53         payload=in.nextInt();
54         Vehicle p1=new Vehicle(wheels,weight);
55         Car p2=new Car(wheels,weight,loader);
56         Truck p3=new Truck(wheels,weight,loader,payload);
57            p1.print();
58            p2.print();
59            p3.print();
60     }
61 
62 }

 

posted @ 2019-04-29 20:50  sky灬刘海波  阅读(266)  评论(0编辑  收藏  举报