Happyr\LinkedIn\LinkedIn::getAccessToken PHP Method

    public function getAccessToken()
    {
        if ($this->accessToken === null) {
            if (null !== ($newAccessToken = $this->getAuthenticator()->fetchNewAccessToken($this->getUrlGenerator()))) {
                $this->setAccessToken($newAccessToken);
            }
        }
        // return the new access token or null if none found
        return $this->accessToken;
    }