code: private static long parseIso8601(String date) {
          SimpleDateFormat formatter = new SimpleDateFormat(
                  "yyyyMMdd'T'HHmmss'Z'");
          formatter.setTimeZone(TimeZone.getTimeZone("UTC"));
          logger.debug("8601date {}", date);
          try {
              return formatter.parse(date).getTime() / 1000;
          } catch (ParseException pe) {
              throw new IllegalArgumentException(pe);
          }
      }
docs: Parse ISO 8601 timestamp into seconds since 1970.