docs: public static int determineConsecutiveDigitCount(CharSequence msg, int startpos) {
      int count = 0;
      int len = msg.length();
      int idx = startpos;
      if (idx < len) {
        char ch = msg.charAt(idx);
        while (isDigit(ch) && idx < len) {
          count++;
          idx++;
          if (idx < len) {
            ch = msg.charAt(idx);
          }
        }
      }
      return count;
    }