code: public static String hexDump(final byte[] array, final int fromIndex, final int length)
      {
          return HexUtil.hexDump(array, fromIndex, length);
      }
docs: Returns a <a href="http://en.wikipedia.org/wiki/Hex_dump">hex dump</a>
  of the specified byte array's sub-region.
  
  @param array     dumped array
  @param fromIndex where should we start to print
  @param length    how much should we print
  @return hex dump in a string representation