Password

/**
 * @author Bruno Alves
 * @version 8/12/2014
 * Generate random password
 */

import java.util.Scanner;


public class Password {


    public static void main(String[] args) {

        Scanner kb = new Scanner(System.in);



        int choice,length,counter = 0,rand, uporlower,num,randpunc;
        char[] lower = {'a','b','c','d','e','f','g','h','i','j','k','l','m','n','o','p','q','u','r','s','t','v','w','x','y','z'}; //26
        char[] upper = {'A','B','C','D','E','F','G','H','I','J','K','L','M','N','O','P','Q','U','R','S','T','V','W','X','Y','Z'};
        char[] punc = {'[',']','(',')','|','{','}','~'}; //8
        String pass = "";

        System.out.println("                Password Generation Menu                ");
        System.out.println("********************************************************");
        System.out.println("*  [1] Lowercase Letters                               *");
        System.out.println("*  [2] Lowercase & Uppercase Letters                   *");
        System.out.println("*  [3] Lowercase, Uppercase, and Numbers               *");
        System.out.println("*  [4] Lowercase, Uppercase, Numbers, and Punctuation  *");
        System.out.println("*  [5] Quit                                            *");
        System.out.println("********************************************************");


        System.out.print("Enter Selection (1-5): ");
        choice = kb.nextInt();
        System.out.println();

        System.out.print("Password Length (1-14): ");
        length = kb.nextInt();
        System.out.println();

        switch(choice)
        {
        case 1:
            while(counter < length)
            {
                rand = 0 + (int)(Math.random()*25);
                pass = pass + lower[rand];
                counter++;
            }
            break;

        case 2:
            while(counter < length)
            {
                uporlower = 0 + (int)(Math.random()*2);
                rand = 0 + (int)(Math.random()*25);
                if (uporlower == 0)
                {
                    pass = pass + lower[rand];
                }
                else
                {
                    pass = pass + upper[rand];
                }
                counter++;
            }
            break;

        case 3:
            while(counter < length)
            {
                uporlower = 0 + (int)(Math.random()*2);
                num = 0 + (int)(Math.random()*9);
                rand = 0 + (int)(Math.random()*25);
                if (uporlower == 0)
                {
                    pass = pass + lower[rand] + num;
                }
                else
                {
                    pass = pass + upper[rand] + num;
                }
                counter++;
            }
            break;

        case 4:
            while(counter < length)
            {
                uporlower = 0 + (int)(Math.random()*2);
                num = 0 + (int)(Math.random()*9);
                rand = 0 + (int)(Math.random()*25);
                randpunc = 0 + (int)(Math.random()*7);
                if (uporlower == 0)
                {
                    pass = pass + lower[rand] + num + punc[randpunc];
                }
                else
                {
                    pass = pass + upper[rand] + num + punc[randpunc];
                }
                counter++;
            }
            break;

        case 5:
            System.out.println("Bye!");
            break;
        }
        System.out.println(pass);
    }

}