lib/classes/Swift/Mime/SimpleMessage.php
public function setSubject($subject)
    {
        if (!$this->setHeaderFieldModel('Subject', $subject)) {
            $this->getHeaders()->addTextHeader('Subject', $subject);
        }

        return $this;
    }
public function setSubject($subject)
    {
        if (!$this->setHeaderFieldModel('Subject', $subject)) {
            $this->getHeaders()->addTextHeader('Subject', $subject);
        }

        return $this;
    }
public function setSubject ( $ subject ) { if ( ! $ this -> setHeaderFieldModel ( 'Subject' , $ subject ) ) { $ this -> getHeaders ( ) -> addTextHeader ( 'Subject' , $ subject ) ; } return $ this ; }
Set the subject of this message.

@param string $subject

@return $this
Set the subject of this message .