public static function preCheck( array &$siteBasics, eZURI $uri )
    {
        if ( !$siteBasics['user-object-required'] )
        {
            return null;
        }

        $ini = eZINI::instance();
        $requireUserLogin = ( $ini->variable( 'SiteAccessSettings', 'RequireUserLogin' ) == 'true' );
        $forceLogin = false;
        if ( eZSession::hasStarted() )
        {
            $http = eZHTTPTool::instance();
            $forceLogin = $http->hasSessionVariable( self::FORCE_LOGIN );
        }
        if ( !$requireUserLogin && !$forceLogin )
        {
            return null;
        }
        return self::checkUser( $siteBasics, $uri );
    }