package com.xt.student.system;

//创建学生类存放信息

public class Student {
//声明变量
private String stuNo;

private String stuName;

private String gender;

private int age;

private int score;

//对变量进行封装

public String getStuNo() {
return stuNo;
}

public void setStuNo(String stuNo) {
this.stuNo = stuNo;
}

public String getStuName() {
return stuName;
}

public void setStuName(String stuName) {
this.stuName = stuName;
}

public String getGender() {
return gender;
}

public void setGender(String gender) {
this.gender = gender;
}

public int getAge() {
return age;
}

public void setAge(int age) {
this.age = age;
}

public int getScore() {
return score;
}

public void setScore(int score) {
this.score = score;
}
//修改toString()方法来输出学生信息，否则输出的为学生信息存储地址
public String toString() {
return "| " + stuNo + " | " + stuName + " | " + gender + " | " + age + " | " + score + " | ";
}

}

//创建一个类实现增删改查

package com.xt.student.system;

public class StuStata {

/**
* 存放学生信息的数组
*/

private static List<Student> stuData = http://www.mamicode.com/new LinkedList();

/**
* 学生数组信息存放标志位
*/

private static int dataIndex = 0;

/**
* 增加学生信息
* 
*/

public void addStu(Student stu){

stuData.add(stu);
dataIndex++;
}

/**
* 根据学生编号删除学生信息
* 当查找到学生信息之后，将查找到的学生以后位置的学生信息向前移一位。

*/

public void delStu(String stuNo){
boolean boo = false;
for(int i = 0;i < dataIndex;i++){
if(stuData.get(i).getStuNo().equals(stuNo)){
stuData.remove(stuData.get(i));
boo = true;
break;
}
}
if(boo){
dataIndex--;
}
}

/**
* 修改学生信息
*/

public void update(Student stu){

for(int i = 0;i< dataIndex; i++){
if(stu.getStuNo().equals(stuData.get(i).getStuNo())){
stuData.set(i, stu);
}
}
}

/**
* 根据学生编号查询学生信息，当有此学生信息时，
* 返回学生信息，当学生信息不存在时，返回 Null
*

public Student getStuByStuNo(String stuNo){

for(int i = 0;i < dataIndex;i++){
if(stuNo.equals(stuData.get(i).getStuNo())){
return stuData.get(i);
}
}
return null;
}

public int getDataIndex(){

return dataIndex;
}

/**
* 获取所有的学生信息

*/

public Student getAllStuInfo(int i){

return stuData.get(i);


}

}

//根据用户输入的信息修改学生信息

package com.xt.student.system;

import java.util.List;
import java.util.Scanner;

public class stuSeverce {

StuStata sd = new StuStata();

public void addStuInfo(Scanner scanner){
Student stu = new Student();
System.out.println("请输入学生编号：");
String stuNo = scanner.next();
if(sd.getStuByStuNo(stuNo) != null){
System.out.println("此学生编号已存在，请选择操作：");
System.out.println("1 继续添加学生信息");
System.out.println("0 退出");
int optional = scanner.nextInt();
switch(optional){
case 0:
return;
case 1:
addStuInfo(scanner);
}
}
stu.setStuNo(stuNo);
System.out.println("请输入学生姓名：");
stu.setStuName(scanner.next());
System.out.println("请输入学生性别(男/女)：");
stu.setGender(scanner.next());
System.out.println("请输入学生年龄：");
stu.setAge(scanner.nextInt());
System.out.println("请输入学生成绩：");
stu.setScore(scanner.nextInt());

sd.addStu(stu);
System.out.println("输入信息成功 \n");

}


public void printAllStuInfo(){
int dataIndex = sd.getDataIndex();
if(dataIndex == 0){
System.out.println("当前无学生信息! \n\n");
}
for(int i = 0; i < dataIndex ;i++){
Student stu = sd.getAllStuInfo(i);
printTitle();
System.out.println(""+stu.toString());
}

}

public void delStuInfo(Scanner scanner){
System.out.println("请输入要删除的学生编号：");
String stuNo = scanner.next();
if(sd.getStuByStuNo(stuNo) == null){
System.out.println("此学生编号不存在，请选择操作：");
System.out.println("1 继续删除学生信息");
System.out.println("0 退出");
int optional = scanner.nextInt();
switch(optional){
case 0:
return;
case 1:
delStuInfo(scanner);
}
}
sd.delStu(stuNo);
System.out.println("删除信息成功！\n");
}

public void updateStuInfo(Scanner scanner){
System.out.println("请输入要修改的学生编号：");
Student stu = new Student();
String stuNo = scanner.next();
if(sd.getStuByStuNo(stuNo) == null){
System.out.println("此学生编号不存在，请选择操作：");
System.out.println("1 继续修改学生信息");
System.out.println("0 退出");
int optional = scanner.nextInt();
switch(optional){
case 0:
return;
case 1:
updateStuInfo(scanner);
}
}
stu.setStuNo(stuNo);
System.out.println("请输入学生姓名：");
stu.setStuName(scanner.next());
System.out.println("请输入学生性别(男/女)：");
stu.setGender(scanner.next());
System.out.println("请输入学生年龄：");
stu.setAge(scanner.nextInt());
System.out.println("请输入学生成绩：");
stu.setScore(scanner.nextInt());

sd.update(stu);
System.out.println("输入信息成功! \n");
}



public void checkStuInfo(Scanner scanner){
System.out.println("请输入所要查询的学生的编号");
String stuNo = scanner.next();
if(sd.getStuByStuNo(stuNo) == null){
System.out.println("此学生编号不存在，请选择操作：");
System.out.println("1 继续查询学生信息");
System.out.println("0 退出");
int optional = scanner.nextInt();
switch(optional){
case 0:
return;
case 1:
updateStuInfo(scanner);
}
}
printTitle();
System.out.println("" + sd.getStuByStuNo(stuNo).toString());
}

public void printTitle(){
System.out.print("| 学生编号 | 学生姓名 | 性别 | 年龄 | 成绩 | \n\n");
}

}

//菜单

package com.xt.student.system;

public class Menu {

public void showmenu(){
System.out.println("1:添加学生信息");
System.out.println("2:修改学生信息");
System.out.println("3:删除学生信息");
System.out.println("4:查询学生信息");
System.out.println("5:查询所有学生信息");
System.out.println("0:退出系统");
}

}

//主方法

package com.xt.student.system;

import java.util.Scanner;

public class Main {
public static void main(String[] args){
Scanner scanner = new Scanner(System.in);
System.out.println(" 欢迎来到学生信息管理系统 ");
Menu menu = new Menu();
stuSeverce stu = new stuSeverce();
while(true){
System.out.println("请按指示进行操作");
menu.showmenu();
int optional = scanner.nextInt();
switch(optional){
case 0:
System.out.println("退出系统");
System.exit(0);
break;
case 1:
stu.addStuInfo(scanner);
break;
case 2:
stu.updateStuInfo(scanner);
break;
case 3:
stu.delStuInfo(scanner);
break;
case 4:
stu.checkStuInfo(scanner);
break;
case 5:
stu.printAllStuInfo();
break;
}
}
}
}

用基本数据结构修改后的学生信息管理系统（增删改查）