java202302java学习笔记第十九天-升级学生管理系统16登录功能

package StudentSys;
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<>();
        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);
                    break;
                }
                case "2": {
                    register(list);
                    break;
                }
                case "3": {
                    forgetPassWord(list);
                    break;
                }
                case "4": {
                    System.out.println("谢谢使用");
                    System.exit(0);
                }
                default:
                    System.out.println("没有这个选项");
            }
        }
    }
    private  static void register(ArrayList<User> list) {
        System.out.println("注册");
        Scanner sc = new Scanner(System.in);
        String username;
        while (true) {
            System.out.println("请输入用户名");
             username = sc.next();
            //用户名必须是3-15位之间
            boolean flag1 = checkUsername(username);
            if (!flag1) {
                System.out.println("当前格式不满足要求,请重新输入");
                continue;
            }
            boolean flag2 = contains(list, username);
            if (flag2) {
                System.out.println("用户名" + username + "已存在");
                continue;
            } else {
                System.out.println("用户名" + username + "可用");
                break;
            }
        }
        String password;
        while (true) {
            System.out.println("请输入密码");
             password = sc.next();
            System.out.println("请再次输入密码");
            String againPassword = sc.next();
            if (!password.equals(againPassword)) {
                System.out.println("两次密码不一致,请重新输入");
                continue;
            } else {
                System.out.println("两次密码一致,请继续输入");
                break;
            }
        }
        //键盘输入身份证号码
        String personId;
        while (true) {
            System.out.println("请输入身份证号码");
             personId = sc.next();
            boolean flag = checkPersonId(personId);
            if (flag) {
                System.out.println("身份证信息满足条件");
                break;
            } else {
                System.out.println("身份证信息不满足条件");
                continue;
            }
        }
        String phoneNumber;
        while (true) {
            System.out.println("请输入手机号码");
             phoneNumber = sc.next();
            boolean flag=checkNumber(phoneNumber);
            if (flag) {
                System.out.println("手机信息满足条件");
                break;
            } else {
                System.out.println("手机信息不满足条件");
                continue;
            }
        }
        User u=new User(username,password,personId,phoneNumber);
        list.add(u);
        printList(list);
        System.out.println("注册成功");
    }
    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());
        }
    }
    private static boolean checkNumber(String phoneNumber) {
        if(phoneNumber.length()!=11){
            System.out.println("手机号必须是18位数字");
            return false;
        }
        if(phoneNumber.startsWith("0")){
            System.out.println("手机号不能是0开头");
            return false;
        }
        for (int i = 0; i < phoneNumber.length()-1; i++) {
            char c=phoneNumber.charAt(i);
            if(!(c>='0'&&c<='9')){
                return false;
            }
        }
        return true;
    }
    private  static  void login(ArrayList<User> list){
        Scanner sc=new Scanner(System.in);
        User useInfo;
        for (int i = 0; i < 3; i++) {
            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");
                return;
            }
            String rightCode=getCode();
            System.out.println("请输入密码");
            String password=sc.next();
             useInfo=new User(username,password,null,null);
            //验证用户名和密码是否正确
            boolean result=checkUserInfo(list,useInfo);
            if(result){
                System.out.println("登录成功");
            }else{
                System.out.println("登录错误");
                if(i==2){
                    System.out.println("多次登录失败 请联系管理员");
                }
            }
            while (true){
                System.out.println("请输入验证码");
                System.out.println(rightCode);
                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;
                }
            }
        }
    }
    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  void forgetPassWord(ArrayList<User> list){
        System.out.println("忘记密码");
    }
    private  static  boolean checkUsername(String username){
        int len=username.length();
        if(len<3||len>15){
            return  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;
            }
        }
        //用户满足内容要求
        //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;
    }
    private static  boolean checkPersonId(String personId){
        if(personId.length()!=18){
            System.out.println("身份证号必须是18位数字");
            return false;
        }
        if(personId.startsWith("0")){
            System.out.println("身份证号不能是0开头");
            return false;
        }
        for (int i = 0; i < personId.length()-1; i++) {
            char c=personId.charAt(i);
            if(!(c>='0'&&c<='9')){
                return false;
            }
        }
        char endChar=personId.charAt(personId.length()-1);
        if((endChar>='0'&&endChar<='9')||(endChar=='x')||(endChar=='X')){
            return true;
        }else{
            return  false;
        }
    }
    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;
           }else{
               return false;
           }
        }
        return  false;
    }
    public static String getCode() {
       //创建一个集合
        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();
        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);
        }
        //随机数字添加到某位
        int number=r.nextInt(10);
        sb.append(number);
        //数字可以再任意位置
        char[] arr=sb.toString().toCharArray();
        int randomIndex=r.nextInt(arr.length);
        //最大索引随机交换
        char temp=arr[randomIndex];
        arr[randomIndex]=arr[arr.length-1];
        arr[arr.length-1]=temp;
        return new String(arr);
    }
}