private static boolean isDateFormatString(String string) {
      if (string.length() < 3) {
        // A string this short is very unlikely to be a date format.
        return false;
      }
      final int strLength = string.length();
      final char startChar = string.charAt(0);
      final char endChar = string.charAt(strLength - 1);
      if (startChar == SLASH || endChar == SLASH) {
        // Most likely it's a filename if the string starts or ends
        // with a slash.
        return false;
      }
      else if (OSAgnosticPathUtil.startsWithWindowsDrive(string)) {
        // Most likely this is a Windows-style full file name.
        return false;
      }
      final Matcher dateFormatMatcher = Holder.DATE_FORMAT_PATTERN.matcher(string);
      return dateFormatMatcher.find();
    }
private static boolean isDateFormatString(String string)