/**
  * Retrieve object using using composite pkey values.
  * @param string $calendar_uid
  * @param string $calendar_business_day
  * @param string $calendar_business_start
  * @param string $calendar_business_end
  * @param      Connection $con
  * @return     CalendarBusinessHours
  */
 public static function retrieveByPK($calendar_uid, $calendar_business_day, $calendar_business_start, $calendar_business_end, $con = null)
 {
     if ($con === null) {
         $con = Propel::getConnection(self::DATABASE_NAME);
     }
     $criteria = new Criteria();
     $criteria->add(CalendarBusinessHoursPeer::CALENDAR_UID, $calendar_uid);
     $criteria->add(CalendarBusinessHoursPeer::CALENDAR_BUSINESS_DAY, $calendar_business_day);
     $criteria->add(CalendarBusinessHoursPeer::CALENDAR_BUSINESS_START, $calendar_business_start);
     $criteria->add(CalendarBusinessHoursPeer::CALENDAR_BUSINESS_END, $calendar_business_end);
     $v = CalendarBusinessHoursPeer::doSelect($criteria, $con);
     return !empty($v) ? $v[0] : null;
 }