Question

Create a program via Java that has atleast 8 characters long, one upper case, and one lower case, and one digit.

here is my code:

    public static void main(String[] args)
    {
        //variables defined
        String passwords;
        char password =0;
       
        //settings up password condition to false
        boolean passwordcondition= false;
        boolean size=false;
        boolean digit=false;
        boolean upper=false;
        boolean lower=false;

        //inputting a scanner into the system
        Scanner keyboard = new Scanner(System.in);
       
            System.out.println("Please enter a password: \n (Caution must have one uppercase, one lowercase, and a digit for password to be valid!)");
            passwords=keyboard.nextLine();
      
            while(!passwordcondition)
            {

                        for (int p=0; p<passwords.length(); p++)
                        {  
                                if(Character.isDigit(p))
                                {
                                  digit = true;  
                                }
                                else if(Character.isUpperCase(p))
                                {
                                  upper = true;
                                }
                                else if(Character.isLowerCase(p))
                                {
                                  lower = true;
                                }
                                else if(passwords.length() > 8)
                                {
                                  size = true;
                                }
                        }
                       
                       
                           if(digit == true && upper == true && lower == true && size == true)
                           {
                             System.out.printf("You have entered a valid password");
                             System.exit(0);
                           }
                           else
                           {
                             System.out.println("You have entered an invalid password");
                             return;
                           }

                       
            }

    }

my problem is I cannot get it back into the loop if I have an invalid answer.

Answer 1

// I have edited the program as required

import java.util.Scanner;
public class pass
{

public static void main(String[] args)
{
//variables defined
String passwords;
char password =0;

//settings up password condition to false
boolean passwordcondition;
boolean size=false;
boolean digit=false;
boolean upper=false;
boolean lower=false;
//inputting a scanner into the system
Scanner keyboard = new Scanner(System.in);

do
{
System.out.println("Please enter a password: \n (Caution must have one uppercase, one lowercase, and a digit for password to be valid!)");
passwords=keyboard.nextLine();
char ch;

for (int p=0; p<passwords.length(); p++)
{
ch=passwords.charAt(p);
if(Character.isDigit(ch))
{
digit = true;  
}
else if(Character.isUpperCase(ch))
{
upper = true;
}
else if(Character.isLowerCase(ch))
{
lower = true;
}
else if(passwords.length() >= 8)
{
size = true;
}
}


if(digit == true && upper == true && lower == true && size == true)
{
System.out.printf("You have entered a valid password");
passwordcondition=true;
System.exit(0);

}
else
{
System.out.println("You have entered an invalid password");
passwordcondition=false;
}

}while(passwordcondition==false);
}
}