Java：Simple Loop

Question

這是一個沒有任何循環的簡單版本。我怎樣才能讓它循環像「錯誤的密碼，再試一次。」直到用戶輸入正確的密碼而不是停止程序 （或者在它停止之前給他們3次機會）？

import java.util.Scanner; 
public class helloworld2 
{ 
    public static void main(String[] arg) 
    { 
     Scanner q = new Scanner(System.in); 
     long Pass; 
     boolean auth = true; 

     System.out.println("Enter Password :"); 
     Pass = q.nextLong(); 

     if (Pass != 1234) 
      { 
      System.out.println("Wrong Password!"); 
      auth = false; 
      } 
     else 
      { 
      System.out.println("Password Confirmed."); 
      auth = true; 
      } 

     if (auth) { 
      ////blablabla 
      } 

     else 
      { 
      return; 
      }     
    } 
} 

Answer 1

public class helloworld2 
{ 
    public static void main(String[] arg) 
    { 
     Scanner q = new Scanner(System.in); 
     long Pass; 
     boolean auth = true; 
     boolean rightPassword = false; 
     while(!rightPassword){//repeat until passwort is correct 
      System.out.println("Enter Password :"); 
      Pass = q.nextLong(); 

      if (Pass != 1234) 
      { 
      System.out.println("Wrong Password!"); 
      auth = false; 
      } 
      else 
      { 
      rightPassword = true;//let the loop finish 
      System.out.println("Password Confirmed."); 
      auth = true; 
      } 
     } 
     // Here do what you want to do 
     //because here the user has entered a right password     
    } 
}