java练习

1．创建一个三角形类，成员变量三边，方法求周长，创建类来测试它。

 1 public class Triangle {
 2 //定义三角形的三个边
 3 private double side1;
 4 private double side2;
 5 private double side3;
 6 private double perimeter;
 7 //构造方法
 8 public Triangle(double s1,double s2,double s3){
 9 side1=s1;
10 side2=s2;
11 side3=s3;
12 }
13 //计算周长的方法
14 public void calculate(){
15 //判断输入的数据是否可以组成三角形
16 if ((side1+side2<side3)||(side1+side3<side2)||(side2+side3<side1)){
17 System.out.println("输入数据不合法");
18 return ;
19 }
20 perimeter=side1+side2+side3;
21 System.out.println("这个三角形的周长为："+perimeter);
22 
23 }
24 
25 public void setSide1(){
26 this.side1=side1;
27 }
28 public double getSide1(){
29 return side1;
30 }
31 public void setSide2(){
32 this.side2=side2;
33 }
34 public double getSide2(){
35 return side2;
36 }
37 public void setSide3(){
38 this.side3=side3;
39 }
40 public double getSide3(){
41 return side3;
42 }
43 }
1 public class TriangleTest {
2     public static void main(String[] args) {
3         Triangle triangle=new Triangle(20.0,1.0,40.0);
4         triangle.calculate();
5     }
6 
7 }

 

2．按要求编写Java应用程序。

（1）创建一个叫做People的类：

属性：姓名、年龄、性别、身高

行为：说话、计算加法、改名

编写能为所有属性赋值的构造方法；

（2）创建主类：

创建一个对象：名叫“张三”，性别“男”，年龄18岁，身高1.80；

让该对象调用成员方法：

说出“你好！”

计算23+45的值

将名字改为“李四”

 1 public class People {
 2     private String peopleName;
 3     private int peopleAge;
 4     private char gender;
 5     private double height;
 6     public People(String name,int age,char g,double h){
 7         peopleName=name;
 8         peopleAge=age;
 9         gender=g;
10         height=h;
11     }
12 
13     public void speak(){
14         System.out.println("你好");
15     }
16     public void calculate(int num1,int num2){
17         System.out.println(num1+num2);
18     }
19     public void rename(String rename){
20         peopleName=rename;
21     }
22 
23     public String getPeopleName() {
24         return peopleName;
25     }
26 
27     public void setPeopleName(String peopleName) {
28         this.peopleName = peopleName;
29     }
30 
31     public int getPeopleAge() {
32         return peopleAge;
33     }
34 
35     public void setPeopleAge(int peopleAge) {
36         this.peopleAge = peopleAge;
37     }
38 
39     public char getGender() {
40         return gender;
41     }
42 
43     public void setGender(char gender) {
44         this.gender = gender;
45     }
46 
47     public double getHeight() {
48         return height;
49     }
50 
51     public void setHeight(double height) {
52         this.height = height;
53     }
54 }

　　

 1 public class PeopleTest {
 2     public static void main(String[] args) {
 3         People people=new People("张三",18,'男',1.80);
 4         System.out.println("姓名："+people.getPeopleName()+"\t"+"年龄："+people.getPeopleAge()+"\t"+"性别："+people.getGender()+"\t"+"身高："+people.getHeight()+"\t");
 5 
 6         people.speak();
 7         people.calculate(23,45);
 8         people.rename("李四");
 9         System.out.println("姓名："+people.getPeopleName()+"\t"+"年龄："+people.getPeopleAge()+"\t"+"性别："+people.getGender()+"\t"+"身高："+people.getHeight()+"\t");
10     }
11 }

 

posted @ 2021-03-16 22:06  程序beginner  阅读(81)  评论(0)    收藏  举报