code: public static String changeFormatAndTimeZoneToOffsetDateTime(
              String dateFormat, String zoneOffsetId, String dateString) {
          return JMOptional.getOptional(zoneOffsetId)
                  .map(id -> getOffsetDateTime(changeTimestampToLong
                          (dateFormat, dateString, id)).toString())
                  .orElseGet(() -> changeFormatAndTimeZoneToOffsetDateTime(
                          dateFormat, dateString));
      }
docs: Change format and time zone to offset date time string.
  
  @param dateFormat   the date format
  @param zoneOffsetId the zone offset id
  @param dateString   the date string
  @return the string