Question

Design a Java program to reset a user's password. The password must consist of exactly six characters, of which one must be a digit, one must be an uppercase letter, and one must be a lowercase letter. Tell the user if the password is correct or if incorrect tell them what is wrong with it. For example, you could say: "Not valid! the password must have 6 characters! Goodbye!"

Can't contain loops.

Using Boolean, String, Int, char

Answer 1

thanks for the question, Here is the code without loops. Have used string, int, boolean, char in the code and also commented the code for you to follow it easily

thank you ! If you are satisfied please rate

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import java.util.Scanner;

public class PasswordReset {


    public static void main(String[] args) {


        Scanner scanner = new Scanner(System.in);
        System.out.print("Enter password: ");
        String password = scanner.nextLine();

        boolean containsDigits = false;
        boolean containsLowerCase = false;
        boolean containsUpperCase = false;

        int passwordLength = password.length();

        // check if the password contains 6 characters
        if (passwordLength != 6) {
            System.out.println("Not valid. Password must have 6 characters! Goodbye!");
        } else {
            // store 6 letters in 6 variables
            char first = password.charAt(0);
            char second = password.charAt(1);
            char third = password.charAt(2);
            char fourth = password.charAt(3);
            char fifth = password.charAt(4);
            char sixth = password.charAt(5);
           
            // check if one of the character is digit
            if (('0' <= first && first <= '9') ||
                    ('0' <= second && second <= '9') ||
                    ('0' <= third && third <= '9') ||
                    ('0' <= fourth && fourth <= '9') ||
                    ('0' <= fifth && fifth <= '9') ||
                    ('0' <= sixth && sixth <= '9')) {
                containsDigits = true;
            }
            // check if one of the character is lower case
            if (('a' <= first && first <= 'z') ||
                    ('a' <= second && second <= 'z') ||
                    ('a' <= third && third <= 'z') ||
                    ('a' <= fourth && fourth <= 'z') ||
                    ('a' <= fifth && fifth <= 'z') ||
                    ('a' <= sixth && sixth <= 'z')) {
                containsLowerCase = true;
            }
            // check if one of the character is upper case
            if (('A' <= first && first <= 'Z') ||
                    ('A' <= second && second <= 'Z') ||
                    ('A' <= third && third <= 'Z') ||
                    ('A' <= fourth && fourth <= 'Z') ||
                    ('A' <= fifth && fifth <= 'Z') ||
                    ('A' <= sixth && sixth <= 'Z')) {
                containsUpperCase = true;
            }

            // if condition to valid password
            if(containsDigits){
                if(containsLowerCase){
                    if(containsUpperCase){
                        System.out.println("Valid. Password Accepted!");
                    }else{
                        System.out.println("Not valid! Password must contain one upper case letter.Goodbye!");
                    }
                }else{
                    System.out.println("Not valid! Password must contain one lower case letter.Goodbye!");
                }
            }else{
                System.out.println("Not valid! Password must contain one digit letter.Goodbye!");
            }

        }
    }
}

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thanks a lot!