public function on_after_delete()
 {
     parent::on_after_delete();
     $oRef = new ReflectionClass($this->getSpiderClassName());
     $oSpider = $oRef->newInstance(array());
     $table = $oSpider->table['table'];
     $rs = Identifiable::getItemById($this->spiderID, $table);
     $oSpider = $oRef->newInstance($rs);
     $oSpider->delete();
 }