/**
 * Copyright (C) 2014 android10.org. All rights reserved.
 * @author Fernando Cejas (the android10 coder)
 */
package com.fernandocejas.android10.rx.sample;

import java.util.Random;

public class RandomStringGenerator {

  private static final int DEFAULT_STRING_LENGHT = 10;
  private static final char[] symbols;

  static {
    StringBuilder tmpSymbols = new StringBuilder();
    for (char ch = 'a'; ch <= 'z'; ch++) {
      tmpSymbols.append(ch);
    }
    symbols = tmpSymbols.toString().toCharArray();
  }

  private final int stringLenght;
  private final char[] charArray;
  private final Random random;

  public RandomStringGenerator() {
    this(DEFAULT_STRING_LENGHT);
  }

  public RandomStringGenerator(int stringLength) {
    this.stringLenght = stringLength;
    this.charArray = new char[this.stringLenght];
    this.random = new Random();
  }

  public String nextString() {
    for (int i = 0; i < charArray.length; i++) {
      charArray[i] = symbols[random.nextInt(symbols.length)];
    }
    return String.valueOf(charArray);
  }
}

@@ -271,17 +271,17 @@
 NGHT = 1
-0
+2
 ;%0A  priv
@@ -395,31 +395,165 @@
 har 
-ch = 'a'; ch %3C= 'z'; ch
+numberChar = '0'; numberChar %3C= '9'; numberChar++) %7B%0A      tmpSymbols.append(numberChar);%0A    %7D%0A    for (char letterChar = 'a'; letterChar %3C= 'z'; letterChar
 ++) 
@@ -578,18 +578,26 @@
 .append(
-ch
+letterChar
 );%0A    %7D

Add numeric char to random string generator.