public static final function setParser($parser)
 {
     try {
         if (!$parser || !is_object($parser)) {
             throw new XmlValidatorException("Invalid input parameter, XmlParser object expected, " . gettype($parser) . " given!");
         } else {
             if (get_class($parser) != "XmlParser") {
                 throw new XmlValidatorException("Invalid input parameter, XmlParser object expected, " . get_class($parser) . " given!");
             }
         }
     } catch (Exception $e) {
         throw $e;
     }
     self::$parser = $parser;
 }