Java作业1

题目:

建立一个学生类，有姓名，学号，3门课成绩，总分等信息，能输入输出学生数据，并能对总分进行排序，打印名次。

1  import java.lang.String;  
 2 import java.util.Scanner;  
 3 import java.util.Arrays;  
 4 import java.util.*;  
 5 //import java.lang.reflect;  
 6 class student implements Comparable  
 7 {  
 8     Scanner a=new Scanner(System.in);  
 9     String name;  
10     int number;  
11     double grade1,grade2,grade3;  
12     double sum;  
13     void get()  
14     {  
15         System.out.println("请输入学生姓名:");  
16         name=a.nextLine();  
17         System.out.println("请输入学生学号:");  
18         number=a.nextInt();  
19         System.out.println("请输入学生课程1成绩:");  
20         grade1=a.nextDouble();  
21         System.out.println("请输入学生课程2成绩:");  
22         grade2=a.nextDouble();  
23         System.out.println("请输入学生课程3成绩:");  
24         grade3=a.nextDouble();  
25         sum=grade1+grade2+grade3;  
26         System.out.println("学生信息录入成功!");          
27     }  
28     void put()  
29     {  
30         System.out.println("学生姓名"+name+" "+"学生学号"+number);  
31         System.out.println("课程1"+" "+grade1);  
32         System.out.println("课程2"+" "+grade2);  
33         System.out.println("课程3"+" "+grade3);  
34         System.out.println("总分"+" "+sum);  
35           
36     }  
37     public int compareTo(Object obj)  
38     {  
39         student p=(student)obj;  
40         if(p.sum>this.sum)  
41             return 1;  
42         else if(p.sum<this.sum)  
43         return -1;  
44         else {return 0;}  
45     }  
46       
47 }  
48 public class aa   
49 {  
50     public static void main(String []args)  
51     {  
52         student a[]=new student[3];  
53         for(int i=0;i<3;i++)  
54         {  
55             a[i]=new student();  
56             a[i].get();  
57         }  
58         Arrays.sort(a);  
59         for(int i=0;i<3;i++)  
60             a[i].put();  
61        
62       
63   
64     }  
65       
66       
67 }