sfCoreAutoload::getInstance PHP Method

    public static function getInstance()
    {
        if (!isset(self::$instance)) {
            self::$instance = new sfCoreAutoload();
        }
        return self::$instance;
    }

 public function renderPdf($data, $pageSize = 'a4', $pageOrientation = 'portrait')
 {
     $previous_error_reporting = ini_get('error_reporting');
     // to avoid the complaining for fixing DOMPDF_FONT_DIR at
     // siwappConfiguration.class.php
     ini_set('error_reporting', E_ALL ^ E_NOTICE);
     $input_data = $this->render($data, true);
     sfCoreAutoload::getInstance()->unregister();
     sfAutoload::getInstance()->unregister();
     if (class_exists('sfAutoloadAgain')) {
         sfAutoloadAgain::getInstance()->unregister();
     }
     require_once sfConfig::get('sf_root_dir') . DIRECTORY_SEPARATOR . 'plugins' . DIRECTORY_SEPARATOR . 'sfDomPDFPlugin' . DIRECTORY_SEPARATOR . 'lib' . DIRECTORY_SEPARATOR . 'sfDomPDFPlugin.class.php';
     $q = new sfDomPDFPlugin($input_data);
     sfCoreAutoload::getInstance()->register();
     sfAutoload::getInstance()->register();
     if (class_exists('sfAutoloadAgain')) {
         sfAutoloadAgain::getInstance()->register();
     }
     $q->setProtocol('http://');
     $q->setHost($_SERVER['HTTP_HOST']);
     $q->setPaper($pageSize, $pageOrientation);
     $q->render();
     ini_set('error_reporting', $previous_error_reporting);
     return $q->getPdf();
 }