/**
  * Checks if the recruiters owns $jobId, and if not, error.
  */
 private static function ownsJob(MongoId $jobId)
 {
     $recruiterId = $_SESSION['_id'];
     if (!JobModel::matchJobRecruiter($jobId, $recruiterId)) {
         self::error("permission denied");
         self::render('notice');
         return false;
     }
     return true;
 }
 public static function isOwned(MongoId $recruiterId, MongoId $applicationId)
 {
     $jobId = self::getJob($applicationId);
     return JobModel::matchJobRecruiter($jobId, $recruiterId);
 }