code: public static String formatBytes (byte[] data) {
      // If the data exists, format it.
      if (data != null) {
        return formatBytes(data, 0, data.length, true);
      }
      // Otherwise, return an empty String as the overloaded method would have done.
      else {
        return "";
      }
    }
docs: Produce a formatted view of a byte array.  Duplicate output lines are
  suppressed to save space.
  <p>
  @param data the byte array to be formatted
  @return the formatted byte array, or an empty StringBuffer if null was passed in.