对象数组练习

 1 package com.atguigu.exer;
 2 
 3 public class StudentTest {
 4     
 5     public static void main(String[] args){
 6         
 7         Student[] stud = new Student[20];//定义对象数组
 8         for(int i = 0;i < stud.length;i++){
 9             stud[i] = new Student();//给对象数组赋值
10             //给类元素赋值
11             stud[i].number = i + 1;
12             stud[i].score = (int)(Math.random() * 101);
13             stud[i].state = (int)(Math.random() * 6 + 1);
14         }
15         
16         for(int i = 0;i < stud.length;i++){
17             if(stud[i].state == 3){
18                 System.out.println(stud[i].info());
19             }
20         }
21         System.out.println("************");
22         //冒泡排序
23         for(int i = 0;i < stud.length - 1;i++){
24             for(int j = 0;j < stud.length - 1 - i;j++){
25                 if(stud[j].score > stud[j+1].score){
26                     //交换两个对象，而不是交换两个分数（属性）
27                     Student temp = stud[j];
28                     stud[j] = stud[j+1];
29                     stud[j+1] = temp;
30                 }
31             }
32         }
33         //遍历
34         for(int i = 0;i < stud.length;i++){
35             System.out.println(stud[i].info());
36         }
37             
38     }
39 }
40 
41 class Student{
42 
43     int number;
44     int state;
45     int score;
46     
47     public String info(){
48         return "年级：" + state + "    学号：" + number + "    成绩：" + score;
49     }
50         
51 }