JAVA---在idea上实现简易的学生管理系统

登录需求

代码实现

APP

package ITswj.test4_学生管理系统;

import java.util.ArrayList;
import java.util.Random;
import java.util.Scanner;

public class APP {

    public static void main(String[] args) {
        ArrayList<User>list=new ArrayList<User>();
        while (true) {
            System.out.println("欢迎来到学生管理系统");
            System.out.println("请选择操作：1-->登录 2-->注册 3-->忘记密码");

            Scanner sc = new Scanner(System.in);
            String choose = sc.next();
            switch (choose) {

                case "1" -> login(list);
                case "2" -> register(list);
                case "3" -> forgetPassword(list);
                case "4"-> {
                    System.out.println("[谢谢使用,再见]");
                    System.exit(0);
                }
                default-> System.out.println("[没有这个选项]");
            }
        }

    }

    //注册
    public static void register(ArrayList<User> list)
    {
        //用户名 密码 身份证  手机号
        //把用户对象添加到集合当中

        //1.键盘录入用户名
        Scanner sc=new Scanner(System.in);
        String username;
        String password;
        String personID;
        String phoneNumber;
        while (true) {
            System.out.println("[请输入用户名]");
             username = sc.next();
            //先验证格式是否正确，然后用户名要唯一
            boolean flag1 = checkUsername(username);

            if (!flag1) {
                System.out.println("[用户名格式不满足，需要重新输入]");
                continue;
            }

            boolean flag2= contains(list,username);

            if(flag2){
                System.out.println("[用户名]"+username+"[已经存在]");
            }else{
                System.out.println("[用户名]"+username+"[可用]");
                break;
            }
        }

        //2.键盘录入密码
        while (true){
            System.out.println("[请输入要注册的密码]");
             password=sc.next();
            System.out.println("[请再次输入要注册的密码]");
            String againPassword=sc.next();
            if(!password.equals(againPassword)){
                System.out.println("[两次密码输入不一致，请重新输入]");
                continue;
            }else{
                System.out.println("[两次密码输入一致，继续录入其他数据]");
                break;
            }

        }

        //3.键盘录入身份证密码
        while (true)
        {
            System.out.println("[请输入身份证号码]");
             personID=sc.next();
            boolean flag=checkPersonID(personID);

            if(flag){
                System.out.println("[身份证号码满足要求]");
                break;
            }else{
                System.out.println("[身份证号码格式错误]");
                continue;
            }

        }

        //4.键盘录入手机号
        while (true){

            System.out.println("请输入手机号码");
            phoneNumber=sc.next();
            boolean flag=checkPhoneNumber(phoneNumber);
            if (flag){
                System.out.println("手机号码格式正确");
                break;
            }else {
                System.out.println("手机号码格式有误，请重新输入");
                continue;
            }
        }

        User u=new User(username,password,personID,phoneNumber);

        list.add(u);
        System.out.println("[注册成功]");
        printList(list);
    }

    //登录
    public static void login(ArrayList<User> list) {
        Scanner sc = new Scanner(System.in);

            System.out.println("[请输入用户名]");
            String username = sc.next();

            boolean flag = contains(list, username);
            if (!flag) {
                System.out.println("[用户名]" + username + "[未注册,请先注册再登录]");
                return;
            }
        for (int i = 0; i < 3; i++) {
            System.out.println("[请输入密码]");
            String password = sc.next();

            while (true) {
                String rightCode = getCode();
                System.out.println("[当前的正确的验证码为：" + rightCode + "]");
                System.out.println("[请输入验证码]");
                String code = sc.next();
                if (code.equalsIgnoreCase(rightCode)) {
                    System.out.println("[验证码正确]");
                    break;
                } else {
                    System.out.println("[验证码错误]");
                    continue;
                }

            }

            User useInfo = new User(username, password, null, null);
            boolean result = checkUserInfo(list, useInfo);

            if (result) {
                System.out.println("[登录成功,可以开始使用学生管理系统了]");
                //启动学生管理系统
                StudentManagement ss=new StudentManagement();
                ss.startStudentSystem();
                break;
            } else {
                System.out.println("[登录失败，用户名或密码错误]");
                if (i == 2){
                    System.out.println("当前账号"+username+"被锁定，请联系swj");
                    //锁定后 直接结束方法
                    return;
                }else {
                    System.out.println("用户名或密码错误，还剩下"+(2-i)+"次机会");
                }
            }
        }
    }

    //忘记密码
    private static void forgetPassword(ArrayList<User> list) {
        Scanner sc=new Scanner(System.in);
        System.out.println("[请输入用户名]");
        String username=sc.next();
        boolean flag=contains(list,username);
        if(!flag){
            System.out.println("[当前用户]"+username+"[未注册，请先注册]");
            return;
        }

        //录入身份证号码和手机号 才能修改密码
        System.out.println("[请输入身份证号码]");
        String personID=sc.next();
        System.out.println("[请输入手机号码]");
        String phoneNumber=sc.next();

        //比较手机号与身份证是否相同
        //需要把用户对象通过索引先获取出来
        int index=findIndex(list,username);
        User user=list.get(index);

        if(!(user.getPersonID().equalsIgnoreCase(personID)
        &&user.getPhoneNumber().equals(phoneNumber)) ){
            System.out.println("[身份证或手机号码输入有误，无法修改]");
            return;
        }
        String password;
        //验证成功，直接修改
        while (true) {
            System.out.println("[请输入新的密码]");
             password = sc.next();
            System.out.println("[请再次输入新的密码]");
            String againPassword = sc.next();
            if (password.equals(againPassword)) {
                System.out.println("[两次密码输入一致]");
                break;
            } else {
                System.out.println("[两次密码输入不一致，请重新输入]");
                continue;
            }
        }

        //直接修改即可
        user.setPassword(password);
        System.out.println("[密码修改成功]");

    }

    private static int findIndex(ArrayList<User> list, String username) {
        for (int i = 0; i < list.size(); i++) {
            User user=list.get(i);
            if(user.getUsername().equals(username)){
                return  i;
            }
        }
        return -1;
    }

    //验证码的生成
    private  static  String getCode()
    {
        //验证码规则
        //长度为5  由4个大小写字母和一位数字，数字可以出现在任意位置

        ArrayList<Character>list=new ArrayList<>();
        for (int i = 0; i < 26; i++) {
            list.add((char)('a'+i));
            list.add((char)('A'+i));
        }

        //构造验证码
        StringBuilder sb=new StringBuilder();
        Random r=new Random();
        for (int i = 0; i < 4; i++) {
            int index=r.nextInt(list.size());
            char c=list.get(index);
            sb.append(c);
        }
        //System.out.println(sb);

        int number= r.nextInt(10);
        sb.append(number);

        char []arr=sb.toString().toCharArray();
        int randomindex=r.nextInt(arr.length);

        char temp=arr[randomindex];
        arr[randomindex]=arr[arr.length-1];
        arr[arr.length-1]=temp;

        return new String(arr);

    }

    private static boolean checkUserInfo(ArrayList<User> list, User useInfo) {

        for (int i = 0; i < list.size(); i++) {
            User user=list.get(i);
            if(user.getUsername().equals(useInfo.getUsername()) && user.getPassword().equals(useInfo.getPassword())){
                return true;
            }
        }
        return  false;

    }

    private static boolean checkUsername(String username) {
        //用户名长度必须要3-15位之间
        int len=username.length();
        if(len<3||len>15){
            return false;
        }
        //继续校验 只能是字母加数字  但是不能是纯数字
        for (int i = 0; i < username.length(); i++) {
            char c=username.charAt(i);
            if( !((c>='a'&&c<='z')||(c>='A'&&c<='Z')||(c>='0'&&c<='9'))){
                return false;
            }
        }

        //不能是纯数字
        int count=0;
        for (int i = 0; i < username.length(); i++) {
            char c=username.charAt(i);
            if( (c>='a'&&c<='z')||(c>='A'&&c<='Z')){
                count++;
                break;
            }
        }
        return  count>0;

    }

    //打印列表
    private static void printList(ArrayList<User> list) {

        for (int i = 0; i < list.size(); i++) {
            User user=list.get(i);
            System.out.println(user.getUsername()+","
            +user.getPassword()+","+user.getPersonID()+","+user.getPhoneNumber());
        }
    }

    //检查电话号码是否正确
    private static boolean checkPhoneNumber(String phoneNumber) {
        //长度为11位；
        if(phoneNumber.length()!=11){
            return  false;
        }
        if(phoneNumber.startsWith("0")) {
            return  false;
        }

        for (int i = 0; i < phoneNumber.length(); i++) {
            char c=phoneNumber.charAt(i);
            if(!(c>='0'&&c<='9')){
                return  false;
            }
        }

        return  true;
    }

    //检查身份证号码
    private static boolean checkPersonID(String personID) {
        //长度必须位18位
        if(personID.length()!=18){
            return  false;
        }

        //不能以0位开头
        if(personID.startsWith("0")){
            return  false;
        }

        //前17位必须是数字
        for (int i = 0; i < personID.length()-1; i++) {
            char c=personID.charAt(i);
            if(!(c>='0'&&c<='9')){
                return  false;
            }

        }
        //最后一位可以是数字 也可以是大小写的X
        char endChar=personID.charAt(personID.length()-1);
        if((endChar>='0'&&endChar<='9')||(endChar=='x')||(endChar=='X')){
            return  true;
        }else {
            return  false;
        }

    }

    //检查集合中是否存在当前元素
    private static boolean contains(ArrayList<User> list, String username) {

        for (int i = 0; i < list.size(); i++) {
            User user=list.get(i);
            String rightUsername=user.getUsername();
            if(rightUsername.equals(username)){
                return true;
            }
        }

        return  false;

    }

}

学生的类

package ITswj.test4_学生管理系统;

public class Student {
    //姓名 年龄 家庭住址
    private String id;
    private  String age;
    private String name;
    private  String address;

    public Student() {

    }

    public Student(String id, String age, String name, String address) {
        this.id = id;
        this.age = age;
        this.name = name;
        this.address = address;
    }

    public String getId() {
        return id;
    }

    public void setId(String id) {
        this.id = id;
    }

    public String getAge() {
        return age;
    }

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

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public String getAddress() {
        return address;
    }

    public void setAddress(String address) {
        this.address = address;
    }
}

学生管理系统

package ITswj.test4_学生管理系统;

import java.util.ArrayList;
import java.util.Scanner;

public class StudentManagement {

    public static void startStudentSystem() {
        ArrayList list=new ArrayList<Student>();
     loop:   while (true) {
            System.out.println("----------------欢迎来到玮嘉学生管理系统-----------------");
            System.out.println("1:添加学生");
            System.out.println("2:删除学生");
            System.out.println("3:修改学生");
            System.out.println("4:查询学生");
            System.out.println("5:退出学生管理系统");
            System.out.println("请输入您的选择: ");
            Scanner sc = new Scanner(System.in);
            String choose = sc.next();

            switch (choose) {
                case "1" -> addStudent(list);
                case "2" -> deleteStudent(list);
                case "3" -> updateStudent(list);
                case "4" -> queryStudent(list);
                case "5" -> {
                    System.out.println("退出学生管理系统");
                  //  break loop;
                    System.exit(0);
                }
                default -> System.out.println("没有这个选项");

            }
        }
    }
    //添加学生
    public static  void addStudent(ArrayList<Student> list){
        Student stu=new Student();
        Scanner sc=new Scanner(System.in);

        String id=null;

        while (true) {
            System.out.println("请输入学生的id");
            id=sc.next();
            boolean flag = contains(list, id);
            if (flag) {
                System.out.println("id已经存在，请重新录入");
            } else {
                stu.setId(id);
                break;
            }
        }

        System.out.println("请输入学生的姓名");
        String name=sc.next();
        stu.setName(name);

        System.out.println("请输入学生的年龄");
        String age= sc.next();
        stu.setAge(age);

        System.out.println("请输入学生的地址");
        String address=sc.next();
        stu.setAddress(address);

        list.add(stu);

        System.out.println("学生信息添加成功");
        //System.out.println("添加学生");
    }
    //删除学生
    public static  void  deleteStudent(ArrayList<Student> list){
        Scanner sc=new Scanner(System.in);
        System.out.println("请输入要删除的id");
        String id=sc.next();

        int index=getIndex(list,id);

        if (index>=0){
            list.remove(index);
            System.out.println("id为"+id+"的学生删除成功");
        }else{
            System.out.println("该id不存在，删除失败");
        }

        //System.out.println("删除学生");
    }
    //更新学生信息
    public static  void  updateStudent(ArrayList<Student> list){
        //System.out.println("修改学生");
        Scanner sc=new Scanner(System.in);
        System.out.println("请输入要修改的学生的id");
        String  id=sc.next();

        int index=getIndex(list,id);

        if (index==-1){
            System.out.println("要修改的id"+id+"不存在");
            return;
        }

        Student stu=list.get(index);

        //输入信息修改元素
        System.out.println("请输入要修改的学生姓名");
        String newName=sc.next();
        stu.setName(newName);

        System.out.println("请输入要修改的学生年龄");
        String newAge=sc.next();
        stu.setAge(newAge);

        System.out.println("请输入要修改的学生家庭住址");
        String newAdress=sc.next();
        stu.setAddress(newAdress);

        System.out.println("学生信息修改成功");
    }
//查询学生信息
    public static  void  queryStudent(ArrayList<Student> list){
        if(list.size()==0){
            System.out.println("当前无学生信息，请添加后再查询");
            return ;
        }
        System.out.println("id\t\t姓名\t\t年龄\t\t家庭住址");
        for(int i=0;i<list.size();i++)
        {
            Student stu=list.get(i);
            System.out.println(stu.getId()+"\t\t"+stu.getName()+"\t\t" +
                    stu.getAge()+"\t\t"+stu.getAddress());
        }

       // System.out.println("查询学生");
    }

    //判断id在集合中是否存在
    public static boolean contains(ArrayList<Student>list,String id){

//        for (int i = 0; i < list.size(); i++) {
//            Student stu=list.get(i);
//            String sid= stu.getId();
//            if(sid.equals(id)){
//                return true;
//            }
//        }
//        return  false;
        return getIndex(list,id)>=0;
    }

    //通过 id 去获取索引
    public static int getIndex(ArrayList<Student>list,String id)
    {
        for (int i = 0; i < list.size(); i++) {
            Student stu=list.get(i);
            String sid=stu.getId();
            if(sid.equals(id)){
                return i;
            }
        }
    return  -1;
    }

}

用户类

package ITswj.test4_学生管理系统;

public class User {
    private String username;
    private String password;
    private String personID;

    private  String phoneNumber;

    public User() {
    }

    public User(String username, String password, String personID, String phoneNumber) {
        this.username = username;
        this.password = password;
        this.personID = personID;
        this.phoneNumber = phoneNumber;
    }

    public String getUsername() {
        return username;
    }

    public void setUsername(String username) {
        this.username = username;
    }

    public String getPassword() {
        return password;
    }

    public void setPassword(String password) {
        this.password = password;
    }

    public String getPersonID() {
        return personID;
    }

    public void setPersonID(String personID) {
        this.personID = personID;
    }

    public String getPhoneNumber() {
        return phoneNumber;
    }

    public void setPhoneNumber(String phoneNumber) {
        this.phoneNumber = phoneNumber;
    }
}