private function sendContent() {
        if ($this->content !== null) {
            if ($this->content instanceof View) {
                $this->content->render();
            }
            else if (($this->content instanceof stdClass) || is_array($this->content)) {
                echo "<pre>";
                print_r ($this->content);
                echo "</pre>";
            }
            else {
                echo $this->content;
            }
        }
    }