public function run()
    {
        if (!$this->isRan) {
            $this->isRan = true;
            foreach ($this->items as $aItem) {
                $mOpt      = isset($aItem[2]) ? $aItem[2] : array();
                $sRuleName = $aItem[1];
                foreach (is_array($aItem[0]) ? $aItem[0] : array($aItem[0]) as $sFieldName) {
                    self::applyRuleToField($sFieldName, $sRuleName, $mOpt);
                }
            }
        }
        return $this;
    }