/**
  * {@inheritdoc}
  */
 public function send($requests)
 {
     $accessToken = $this->provider->getAccessToken();
     if (!$requests instanceof RequestInterface) {
         /** @var $requests RequestInterface[] */
         foreach ($requests as &$request) {
             $this->addTokenHeader($request, $accessToken);
             $this->addJsonContentTypeHeader($request);
         }
         return $this->sendMultiple($requests);
     }
     $this->addTokenHeader($requests, $accessToken);
     $this->addJsonContentTypeHeader($requests);
     return parent::send($requests);
 }
 /**
  * @param AccessTokenProviderInterface $accessTokenProvider
  */
 public function setAccessTokenProvider(AccessTokenProviderInterface $accessTokenProvider)
 {
     $this->accessTokenProvider->setProvider($accessTokenProvider);
 }