Thread: learning while and for loops

Hello!

My name is Jon and I am taking my first programming class in Java. I have to write a program that asks the user to enter a "new password." The program should check that the user's password has at least one uppercase letter, one lowercase letter, and one non-letter character. Furthermore, if the user enters an incorrect password, the program should keep asking for a new password until it gets a valid one. if the use enters an incorrect password 3 times, the program stops asking the user for a new password.

I'm sure there are 999 different ways to write this code. I'm really close with what I have, so I'm hoping I don't have to change everything around entirely. my code can correctly test whether the user's password is valid or not. i'm having trouble getting it to ask the user for a new pw if it is not valid the first time. Anyway, here's what I have so far!

import java.util.*;
 
public class HWHelp
{
	public static void main (String [] args)
	{
		boolean hasUpper = false;
		boolean hasLower = false;
		boolean hasNonLetter = false;
		boolean passwordSet = false;
		Scanner scan = new Scanner(System.in);
		System.out.println("Please enter a new password. Make sure your password "
			+ "contains at least one uppercase letter, one lowercase letter, "
			+ "and at least one character that is either a numerical digit or other "
			+ "non-letter.");
 
		String usersPw = scan.next();
		int j = 0;
 
		while (!passwordSet && (j < 3))
		{
			for (int i = 0; i < usersPw.length(); i++)
			{	
				while (i < usersPw.length())
				{
					char character = usersPw.charAt(i);
					if (character >= 65 && character <= 90)
					{
						hasUpper = true;
					}
					if (character >= 97 && character <= 122)
					{
						hasLower = true;
					}
					if (character < 65 || (character > 90 && character < 97) || character > 122)
					{
						hasNonLetter = true;
					}
					i++;
				}			
			}
			if (hasUpper && hasLower && hasNonLetter)
			{
				passwordSet = true;
			}
			else
			{
				passwordSet = false;
			}
			j++;
		}
		if (passwordSet)
		{
			System.out.println("Password set.");
		}
		else
		{
			System.out.println("Password change aborted.");
		}
	}
}

Thank you! I figured it out! That was a big help.

JG