private function _getValidLengthJsPart(__IComponent &$component)
 {
     $return_value = '';
     $length_parameters = array();
     $valid_length = $component->getValidLength();
     if ($valid_length != null) {
         $length_parameters[] = 'is: ' . $valid_length;
     } else {
         $min_length = $component->getMinLength();
         if ($min_length != null) {
             $length_parameters[] = 'minimum: ' . $min_length;
         }
         $max_length = $component->getMaxLength();
         if ($max_length != null) {
             $length_parameters[] = 'maximum: ' . $max_length;
         }
     }
     if (count($length_parameters) > 0) {
         $return_value = $component->getId() . '.add(Validate.Length, {' . join(', ', $length_parameters) . '});' . "\n";
     }
     return $return_value;
 }