static int toUnicodeChar(@NotNull CharSequence text, int pos, int length) {
      if (length > 1) {
        CharSequence s = text.subSequence(pos + 2, Math.min(text.length(), pos + length + 1));
        try {
          return Integer.parseInt(s.toString(), 16);
        }
        catch (NumberFormatException e) {
          return '?';
        }
      }
      else {
        final Integer result = ESC_TO_CODE.getValue().get(text.charAt(pos + 1));
        return ObjectUtils.notNull(result, (int)text.charAt(pos + 1));
      }
    }
static int toUnicodeChar(@NotNull CharSequence text, int pos, int length)