public static function create($name, $location, $message, $tinyUrl = null)
{
$visitor = new Visitor(null);
$visitor->setName($name);
$visitor->setLocation($location);
$visitor->setMessage($message);
$visitor->setTinyUrl($tinyUrl);
$visitor->setGeneratedId($visitor->generateId());
$visitor->setId($visitor->save());
return $visitor;
}