java 提问帮忙一下
设计一个类Student,该类包括姓名、学号和成绩。设计一个方法,按照成绩从高到低的顺序输出姓名、学号和成绩信息。
------解决方案--------------------package qhxz0405; 
 /*5.设计一个类Student,该类包括姓名、学号和成绩。 
  * 设计一个方法,按照成绩从高到低的顺序输出姓名、学号和成绩信息。 
  * */ 
 public class Student { 
          String name; 
         int number; 
        double grade;          
        Student( String name,int number,double grade){ 
        this.name=name; 
        this.number=number; 
        this.grade=grade; 
        } 
 	public  double getGrade() {		 
 		return grade; 
 	} 
 	public void setGrade(double grade) { 
 		this.grade = grade; 
 	} 
 	  String getName() { 
 		return name; 
 	} 
 	public void setName(String name) { 
 		this.name = name; 
 	} 
 	public  int getNumber() { 
 		return number; 
 	} 
 	public void setNumber(int number) { 
 		this.number = number; 
 	}  	  	 
        void show(){           
     	   System.out.println( "姓名: "+name+ "\t学号: "+number+ "\t成绩: "+grade); 
        }        
 }     
 package qhxz0405;   
 public class Demo {   
 	public static void main(String[] args) { 
 		Student t; 
 		Student[] a = { new Student( "张三 ", 1101, 89), 
 				new Student( "李四 ", 1102, 91), new Student( "王二 ", 1103, 99), 
 				new Student( "孙一 ", 1104, 100) }; 
 		for (int i = 0; i  < a.length; i++) { 
 			for (int j = i; j  < a.length; j++) { 
 				if (a[i].grade  < a[j].grade) { 
 					t = a[i]; 
 					a[i] = a[j]; 
 					a[j] = t; 
 				} 
 			} 
 		} 
 		for (int i = 0; i  < a.length; i++) { 
 			a[i].show(); 
 		}   
 	} 
 }