voku / swiftmailer

     *

     * @return string

     */

    public function toString()

    {

        if (empty($this->headerSigners) && empty($this->bodySigners)) {

            return parent::toString();

        }

        $this->saveMessage();

        $this->doSign();

        $string = parent::toString();

        $this->restoreMessage();

        return $string;

    }

    /**

     * Write this message to a {@link Swift_InputByteStream}.

     *

     * @param Swift_InputByteStream $is

     */

    public function toByteStream(Swift_InputByteStream $is)

    {

        if (empty($this->headerSigners) && empty($this->bodySigners)) {

            parent::toByteStream($is);

            return;

        }

        $this->saveMessage();

        $this->doSign();

        parent::toByteStream($is);

        $this->restoreMessage();

    }

    public function __wakeup()

    {