Full version of student information management system (JAVA)

To create a student management system, first define a class, the code is as follows:

package com.jiang.StudentSystem;

public class Student {
    //id,name,age,address
    private String id;
    private String name;
    private int age;
    private String address;

    public Student() {
    }

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

    public String getId() {
        return id;
    }

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

    public String getName() {
        return name;
    }

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

    public int getAge() {
        return age;
    }

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

    public String getAddress() {
        return address;
    }

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

Student management system, the code is as follows:

package com.jiang.StudentSystem;

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

public class StudentSystem {
    public static void startStudentSystem() {
        ArrayList<Student> list = new ArrayList<>();
        loop:
        while (true) {
            System.out.println("----------------欢迎来到学生管理系统-------------------");
            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");
            Scanner sc = new Scanner(System.in);
            System.out.println("请输入您的选择:");
            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");
                    break loop;
                }
                default -> System.out.println("没有这个选项");
            }
        }
    }

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

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

        }

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

        System.out.println("请输入学生的年龄:");
        int age = sc.nextInt();
        s.setAge(age);
        System.out.println("请输入学生的地址:");
        String address = sc.next();
        s.setAddress(address);

        //把学生添加到集合当中
        list.add(s);


        System.out.println("学生信息添加成功");
    }

    //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("id不存在,删除失败");
        }

    }

    //修改学生
    public static void updateStudent(ArrayList<Student> list) {
        Scanner sc = new Scanner(System.in);
        System.out.println("请输入要修改的学生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,请重新输入");
            return;
        }
        //获取要修改的对象
        Student stu = list.get(index);

        //输入其他信息并修改
        System.out.println("请输入要修改的学生姓名");
        String newName= sc.next();
        stu.setName(newName);

        System.out.println("请输入要修改学生的年龄");
        int newAge = sc.nextInt();
        stu.setAge(newAge);

        System.out.println("请输入要修改的学生的地址");
        String newAddress = sc.next();
        stu.setAddress(newAddress);

        System.out.println("学生信息修改成功");

    }

    //查询学生
    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年龄\t住址");
        for (int i = 0; i < list.size(); i++) {
            Student stu = list.get(i);
            System.out.println(stu.getId() + "\t" + stu.getName() + "\t" + stu.getAge() + "\t" + stu.getAddress());
        }

    }

    //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;
    }

    //通过id获取索引的方法
    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;
    }

}

Create another student management system login interface, the code is as follows:

package com.jiang.StudentSystem;

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) {
        phoneNumber = phoneNumber;
    }
}

Create the student management system login registration page (this code has called the student management system), the code is as follows:

package com.jiang.StudentSystem;

import jdk.swing.interop.SwingInterOpUtils;

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

public class App {
    public static void main(String[] args) {
        ArrayList<User> list = new ArrayList<>();
        Scanner sc = new Scanner(System.in);

        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 4退出");
            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");
                    //退出系统设置
                    System.exit(0);
                }
                default -> System.out.println("没有这个选项");

            }
        }


    }

    private static void forgetPassword(ArrayList<User> list) {
        System.out.println("忘记密码");
        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");
            return;
        }
        //若用户名存在,则继续下面操作
        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();


        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);
        //比较用户对象中的手机号码和身份证号码是否相同
        if (!(user.getPersonID().equals(personID)&&user.getPhoneNumber().equals(phoneNumber))){
            System.out.println("身份证号码或者手机号码有误,不能修改密码");
            return;
        }
        //当代码执行到这里，表示所有的数据全部验证成功，直接修改即可
        String newPassWord;
        while (true) {
            System.out.println("请输入新的密码");
            newPassWord = sc.next();
            System.out.println("请再次输入密码");
            String againNewPassWord = sc.next();
            if (newPassWord.equals(againNewPassWord)){
                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;
            }
        }
        //直接修改密码
        user.setPassWord(newPassWord);
        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;
    }

    private static void register(ArrayList<User> list) {
        System.out.println("注册");
        //键盘录入用户名
        Scanner sc = new Scanner(System.in);
        String userName;
        while (true) {
            System.out.println("请输入用户名");
            userName = sc.next();
            //用户名要求:
            //1.用户名长度必须在3~15位之间
            //2.只能是字母加数字的组合，但是不能是纯数字

            boolean flag1 = checkUsername(userName);
            if (!flag1) {
                System.out.println("用户名格式不满足条件，需要重新输入");
                continue;
            }
            //3.唯一性
            boolean flag2 = contains(list, userName);
            if (flag2) {
                System.out.println("用户名" + userName + "已存在,请重新录入");
            } else {
                System.out.println("用户名" + userName + "可用");
                break;
            }
        }
        //密码键盘输入两次，两次一致才可以进行注册
        String passWord;
        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("两次输入的密码不一致,请重新输入");
            } else {
                System.out.println("两次密码一致,请继续录入其他信息");
                break;
            }
        }
        //键盘录入身份证号码
        String personID;
        while (true) {
            System.out.println("请输入身份证号码");
            personID = sc.next();
            boolean flag3 = checkPersonID(personID);
            if (flag3) {
                System.out.println("身份证号码满足要求");
                break;
            } else {
                System.out.println("身份证号码输入有误,请重新输入");
                continue;
            }
        }
        //键盘录入手机号码
        String phoneNumber;
        while (true) {
            System.out.println("请输入手机号码");
            phoneNumber = sc.next();
            boolean flag4 = checkPhoneNumber(phoneNumber);
            if (flag4) {
                System.out.println("手机号码格式正确");
                break;
            } else {
                System.out.println("手机号码格式错误,请重新输入");
                continue;
            }
        }
        //用户名，密码，身份证号码，手机号码放到用户对象中
        User u = new User(userName, passWord, personID, phoneNumber);
        //把用户对象添加到集合中
        list.add(u);
        System.out.println("注册成功");
        //遍历
        printList(list);
    }

    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());
        }
    }
    //遍历集合


    private static boolean checkPhoneNumber(String phoneNumber) {
        //长度必须为11位
        if (phoneNumber.length() != 11) {
            return false;
        }
        //不能以0开头
        if (phoneNumber.startsWith("0")) {
            return false;
        }
        //必须为数字
        for (int i = 0; i < phoneNumber.length(); i++) {
            char c = phoneNumber.charAt(i);
            if (c < '0' && c > '9') {
                return false;
            }
        }
        return true;
    }

    private static boolean checkPersonID(String personID) {

        //长度为18
        if (personID.length() != 18) {
            return false;
        }
        //不能以0开头
        if (personID.startsWith("0")) {
            //如果以0开头,直接false
            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,也可以是大写X或小写x
        char c = personID.charAt(personID.length() - 1);
        if ((c >= '0' && c <= '9') || (c == 'X' || c == 'x')) {
            return true;
        } else {
            return false;
        }
    }

    private static boolean contains(ArrayList<User> list, String userName) {
        //唯一性
        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;
    }

    private static boolean checkUsername(String userName) {
        //用户名长度必须在3~15位之间
        int len = userName.length();
        if ((len < 3) || (len > 15)) {
            return false;
        }
        //当代码执行到这里，表示用户名的长度是符合要求的。
        //继续校验：只能是字母加数字的组合
        //循环得到username里面的每一个字符，如果有一个字符不是字母或者数字，那么就返回false
        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;
            }
        }
        //当代码执行到这里,表示什么？
        //用户名满足两个要求：1长度满足 2内容也满足（字母+数字）
        //但是不能是纯数字
        //统计在用户名中，有多少字母就可以了。
        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++;
            }
        }
        return count > 0;


    }

    private static void login(ArrayList<User> list) {
        System.out.println("登录");
        //键盘录入用户名
        Scanner sc = new Scanner(System.in);
        for (int i = 0; i < 3; i++) {
            System.out.println("请输入用户名");
            String userName = sc.next();
            //判断用户名是否注册
            boolean flag = contains(list, userName);
            if (!flag) {
                System.out.println("用户名" + userName + "未注册,请先注册");
                continue;
            }
            System.out.println("请输入密码");
            String password = sc.next();

            while (true) {
                String rightCode = getCode();
                System.out.println("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("验证码有误,请重新输入");
                    continue;
                }
            }
            //验证用户名和密码是否正确
            //集合中是否包含用户名和密码
            //定义一个方法验证用户名和密码是否正确
            //封装思想的应用：
            //我们可以把一些零散的数据，封装成一个对象
            //以后传递参数的时候，只要传递一个整体就可以了，不需要管这些零散的数据
            User userInfo = new User(userName, password, null, null);
            boolean result = checkUserInfo(list, userInfo);
            if (result) {
                System.out.println("登陆成功,可以开始使用学生管理系统了");
                //创建对象调用方法，启动学生管理系统
                StudentSystem ss=new StudentSystem();
                ss.startStudentSystem();
                break;
            } else {
                System.out.println("登陆失败,用户名或密码错误");
                if (i == 2) {
                    System.out.println("当前账号" + userName + "被锁定,请联系安徽新华学院客服:05553-459867");
                    //当前账号被锁定,直接结束
                    return;
                } else {
                    System.out.println("用户名或密码错误，还剩下" + (2 - i) + "次机会");
                }
            }
        }

    }

    private static boolean checkUserInfo(ArrayList<User> list, User userInfo) {
        //遍历集合，判断用户是否存在，如果存在登录成功，如果不存在登录失败
        for (int i = 0; i < list.size(); i++) {
            User user = list.get(i);
            if (user.getUsername().equals(userInfo.getUsername()) && user.getPassWord().equals(userInfo.getPassWord())) {
                return true;
            }
        }
        return false;
    }


    private static String getCode() {
        //1.创建一个集合,添加所有大小写字母
        ArrayList<Character> list = new ArrayList<>();
        for (int i = 0; i < 26; i++) {
            list.add((char) ('a' + i));
            list.add((char) ('A' + i));
        }

        StringBuilder sb = new StringBuilder();
        //随机获取四个字母
        Random r = new Random();
        for (int i = 0; i < 4; i++) {
            //获取随机索引
            int index = r.nextInt(list.size());
            //利用随机索引获取字符
            char c = list.get(index);
            //把随机字符添加到sb中
            sb.append(c);
        }
        //把一个随机数添加到末尾
        int number = r.nextInt(10);
        sb.append(number);

        //4.如果我们要修改字符串中的内容
        //先把字符串变成字符数组，在数组中修改，然后再创建一个新的字符串
        char[] arr = sb.toString().toCharArray();
        //用最后一个索引跟随即索引交换
        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);
    }
}

The final running result of the code is as follows;