WorklistManager::getGenerationTimeLimitDate PHP Method

    public function getGenerationTimeLimitDate()
    {
        $limit = $this->getAppParam('worklist_default_generation_limit') ?: self::$DEFAULT_GENERATION_LIMIT;
        $interval = DateInterval::createFromDateString($limit);
        $now = new DateTime();
        return $now->add($interval);
    }

 /**
  * @param $horizon
  *
  * @return DateTime
  */
 public function getDateLimit($horizon)
 {
     if ($horizon) {
         $interval = DateInterval::createFromDateString($horizon);
         $now = new DateTime();
         $limit = clone $now;
         $limit->add($interval);
         if ($limit <= $now) {
             $this->usageError("Invalid horizon string {$horizon}");
         }
         return $limit;
     }
     return $this->manager->getGenerationTimeLimitDate();
 }