用java编一个学生成绩排序成绩 有学生的姓名 学号 三门课的成绩 然后对总分排序

import java.util.*;

public class student

{

class Node

{

public String name ;

public String ID;

public int java ;

public int os;

public int PE;

public int total;

}

public  Node data;

public student next;

public student creat()

{

student head,p,r,s1;

int x1,x2,x3,x4;

String n,i;

head=r=null;

System.out.print("请输入学生的姓名  学号   java成绩    os成绩     Internet 成绩");

System.out.print("请输入一个x整形数据以0结束：");

Scanner c= new Scanner(System.in);

n=c.nextLine();

Scanner c0= new Scanner(System.in);

i=c0.nextLine();

Scanner c1= new Scanner(System.in);

x1=c1.nextInt();

Scanner c2= new Scanner(System.in);

x2=c2.nextInt();

Scanner c3= new Scanner(System.in);

x3=c3.nextInt();

while (x1!=0)

{

student s11=new student();

s11.data.name=n;

s11.data.ID=i;

s11.data.java=x1;

s11.data.os=x2;

s11.data.PE=x3;

s11.data.total=s11.data.java+s11.data.os+s11.data.PE;

if(head==null)

head=s11;

else

r.next=s11;

r=s11;

Scanner b= new Scanner(System.in);

n=b.nextLine();

Scanner b0= new Scanner(System.in);

i=b0.nextLine();

Scanner b1= new Scanner(System.in);

x1=b1.nextInt();

Scanner b2= new Scanner(System.in);

x2=b2.nextInt();

Scanner b3= new Scanner(System.in);

x3=b3.nextInt();

}

if(r!=null)

r.next=null;

return head;

}

public void out(student head)

{

student p;

p=head;

System.out.print("List is:");

while(p!=null)

{

System.out.println("\t"+p.data.name+"\t"+p.data.ID+"\t"+p.data.java+"\t"+p.data.os+"\t"+p.data.PE+"\t"+p.data.total);

p=p.next;

}

}

public student sortup(student head)

{

student p=head,pre=null,s=null,q=null;

head.next=null;

while(p!=null)

{

s=p;

p=p.next;

pre=head;

q=head.next;

while(q!=null && q.data.total

{

pre=q;

q=q.next;

}

s.next=q;

pre.next=s;

}

return head;

}

public student sortdown(student head)

{

student p=head,pre=null,s=null,q=null;

head.next=null;

while(p!=null)

{

s=p;

p=p.next;

pre=head;

q=head.next;

while(q!=null && q.data.total

{

pre=q;

q=q.next;

}

s.next=q;

pre.next=s;

}

return head;

}

public static void main(String[] args) {

student x,y;

student a=new student();

x=a.creat();

a.out(x);

a.sortdown(x);

a.out(x);

a.sortup(x);

a.out(x);

}

}

我是一个java初学者  我们老师布置了一个实验  用java编一个学生成绩管理的一个小程序 (学生人数为10人)

要求：输入姓名  学号  三门课的成绩  计算总成绩  然后对这10个学生的总成绩排序  我编了一个但是行不通 我是按c语言  链表的思想来用java做的  不知道那出了问题  求各位大侠不胜赐教  帮我把它该对  谢谢 ！小女子不胜感激  ！！！  4.30之前就要交 希望大侠们.。。。----------------解决方案--------------------------------------------------------

程序代码：

/**定义一个学生的实体类*/

public class Student {

private String name;

private String ID;

private int java = 0;

private int os = 0;

private int PE = 0;

private int total = 0;

public Student() {

}

public Student(String name,String ID,int java, int os, int PE) {

this.name = name;

this.ID = ID;

this.java = java;

this.os = os;

this.PE = PE;

this.total = java + os + PE;

}

public String getName() {

return name;

}

public void setName(String name) {

this.name = name;

}

public String getID() {

return ID;

}

public void setID(String iD) {

ID = iD;

}

public int getJava() {

return java;

}

public void setJava(int java) {

this.java = java;

}

public int getOs() {

return os;

}

public void setOs(int os) {

this.os = os;

}

public int getPE() {

return PE;

}

public void setPE(int pE) {

PE = pE;

}

public int getTotal() {

return total;

}

public void setTotal(int total) {

this.total = total;

}

public void out(){

System.out.println("\t"+this.getJava()+"\t"+this.getOs()+"\t"+this.getPE()+"\t"+this.getTotal());

}

}

---  下面是 运行方法 ----

public static void main(String[] args) {

/**ArrayList需要通过collections类的sort方法来进行排序

如果想自定义排序方式则需要有类来实现Comparator接口并重写compare方法

调用sort方法时将ArrayList对象与实现Commparator接口的类的对象作为参数**/

Comparator comparator = new Comparator() {

public int compare(Student s1, Student s2) {

return s2.getTotal()-s1.getTotal() ;

//s2.getTotal()-s1.getTotal()倒序//s1.getTotal()-s2.getTotal()顺序

}

};

ArrayList list = new ArrayList();

for (int i = 0; i <= 2; i++) {

Scanner scan = new Scanner(System.in);

System.out.println("请输入学生的姓名  学号   java成绩    os成绩     Internet 成绩");

Student s = new Student(scan.next(),scan.next(),scan.nextInt(), scan.nextInt(),

scan.nextInt());

list.add(s);

}

Collections.sort(list,comparator);

for (Student stu : list) {

stu.out();

}

}

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谢谢

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非常感谢你给我的解答  有些地方我看不怎么懂  再次向你请教

为什么每一个Student的类的每一个属性都有   return xx  ，this.xx=xx 呢？是什么含义

public String getName() {

return name;

}

public void setName(String name) {

this.name = name;

}

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这个是实体类属性的set和get方法！设置值用set获取值用get。

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我定义的属性是private

只能提供一个外部的获取方法才能 获取和修改

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楼上的小程序写的合理，就是此程序不需要它的set get方法，没有涉及到实体注入，同时建议初学者将实体类和主方法分开写，逐渐培养良好的封装思想

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厉害，没想到用这个

Comparator comparator = new Comparator() {

public int compare(Student s1, Student s2) {

return s2.getTotal()-s1.getTotal() ;

//s2.getTotal()-s1.getTotal()倒序 //s1.getTotal()-s2.getTotal()顺序

}

};

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