/*
    * Created by IntelliJ IDEA.
    * User: mike
    * Date: Jan 23, 2002
    * Time: 6:10:02 PM
    * To change template for new class use
    * Code Style | Class Templates options (Tools | IDE Options).
    */
   package com.atlassian.core.util;
  
  public class RandomGenerator {
      /**
       * Generate a random password (length 6)
       */
      public static String randomPassword() {
          return randomString(6);
      }
  
      /**
       * Generate a random string of characters - including numbers
       */
      public static String randomString(int length) {
          return randomString(length, true);
      }
  
      /**
       * Generate a random string of characters
       */
      public static String randomString(int length, boolean includeNumbers) {
          StringBuilder b = new StringBuilder(length);
  
          for (int i = 0; i < length; i++) {
              if (includeNumbers)
                  b.append(randomCharacter());
              else
                  b.append(randomAlpha());
          }
  
          return b.toString();
      }
  
      /**
       * Generate a random alphanumeric character.
       *
       * 3/4rs of the time this will generate a letter, 1/4 a number
       */
      public static char randomCharacter() {
          int i = (int) (Math.random() * 3);
          if (i < 2)
              return randomAlpha();
          else
              return randomDigit();
      }
  
      /**
       * Generate a random character from the alphabet - either a-z or A-Z
       */
      public static char randomAlpha() {
          int i = (int) (Math.random() * 52);
  
          if (i > 25)
              return (char) (97 + i - 26);
          else
              return (char) (65 + i);
      }
  
      /**
       * Generate a random digit - from 0 - 9
       */
      public static char randomDigit() {
          int i = (int) (Math.random() * 10);
          return (char) (48 + i);
      }
  }