创建一个帐户并使用构造函数登录

Question

用户将创建一个帐户，用户将登录。 用户可以创建多个帐户。 在密码或用户名中输入错误的登录输出错误。 我的问题是每当我创建一个帐户并登录时，它不会读取我在创建帐户中输入的内容，并且不断强制用户在登录时输入有效的用户名和密码。

static JavaBank user = new JavaBank(); 
int accountNumber = 1000; 
int initialDeposit; 
String name; 
private String username; 
int pincode; 
int verify; 

public JavaBank(){ 
    accountNumber = 1000; 
    name = "name"; 
    username = "username"; 
    pincode = 1000; 
    verify = 1000; 
    initialDeposit = 5000; 
} 

public JavaBank(int accountNumber, String username, String name, int pincode, int verify, int initialDeposit){ 
    this.username = username; 
    this.accountNumber = accountNumber; 
    this.name = name; 
    this.pincode = pincode; 
    this.verify = verify; 
    this.initialDeposit = initialDeposit; 
} 

public static void main(String args[]){ 
    while(true){ 
    Scanner input = new Scanner(System.in); 
    String tempUsername; 
    int tempPass; 
    int counter = 0; 
    int option; 
    int valid1 = 1; 
    int valid; 
    int login = 0; 
    JavaBank newUser[] = new JavaBank[10]; 

    System.out.println("\nJAVA BANK\n"); 
    System.out.println("[1] Create Account"); 
    System.out.println("[2] Login Account"); 
    System.out.println("[3] Exit\n"); 
    System.out.print("Option: "); 
    option = input.nextInt(); 

    switch(option){ 
     case 1: 
      System.out.println("\n[1] Create Account\n"); 
      System.out.println("Account Number: "+user.accountNumber); 
      System.out.print("Account Name: "); 
      user.name = input.next(); 
      System.out.print("Username: "); 
      user.username = input.next(); 
      do{ 
      valid = 0; 
      System.out.print("Pincode: "); 
      user.pincode = input.nextInt(); 
      if(user.pincode < 1000 || user.pincode > 9999){ 
       valid = 1; 
       System.out.println("Pincode should be 4 digit! Please try again!"); 
       continue; 
      } 
      System.out.print("Verify Pincode: "); 
      user.verify = input.nextInt(); 
      if(user.verify < 1000 || user.verify > 9999){ 
       valid = 1; 
       System.out.println("Pincode should be 4 digit! Please try again!"); 
       continue; 
      } 
      if(user.pincode != user.verify){ 
       valid = 1; 
       System.out.println("Pincode does not match! Please try again!"); 
      } 
      }while(valid!=0); 
      do{ 
      valid = 0; 
      System.out.print("Initial Deposit[Min. of 5000]: "); 
      user.initialDeposit = input.nextInt(); 
      if(user.initialDeposit <5000){ 
       valid = 1; 
       System.out.println("You entered less than 5000! Please try again!"); 
      } 
      System.out.println("\nCongratulations!"); 
      System.out.println("Your account has been created succesfully!"); 
      }while(valid!=0); 
      newUser[counter] = new JavaBank(user.accountNumber++, user.username, user.name, user.pincode, user.verify, user.initialDeposit); 
      counter++; 
      break; 
     case 2: 
      do{ 
      System.out.print("Username: "); 
      tempUsername = input.next(); 
      System.out.print("Pincode: "); 
      tempPass = input.nextInt(); 
      for(int index=0; index<counter; index++){ 
       if(tempUsername.equals(newUser[index].username)){ 
        if(tempPass == newUser[index].pincode) 
         { 
          valid1 = 0; 
          login = index; 
         } 
       } 
      } 
      if(valid1!=0){ 
       System.out.println("Username or password does not exist. Please try again!"); 
      } 
      }while(valid1!=0); 

Answer 1

您需要同时移动user[]和counter从main()为静态变量。

public class JavaBank { 
    static JavaBank user = new JavaBank(); 
    int accountNumber = 1000; 
    int initialDeposit; 
    String name; 
    private String username; 
    int pincode; 
    int verify; 
    private static int counter = 0;//Add here and remove from main() 
    private static JavaBank newUser[] = new JavaBank[10];//add here and remove from main() 

    public JavaBank() { 
     accountNumber = 1000; 
     name = "name"; 
     username = "username"; 
     pincode = 1000; 
     verify = 1000; 
     initialDeposit = 5000; 
    } 
. 
. 
. 

这是怎么回事。您递增计数器，当您再次输入选项时，计数器值和用户将丢失。当您将它们制作为static时，它可用，直到程序存在。