src/Core/OAuth/OAuth2/OAuth2LoginHelper.php
public function getAccessToken(){
       if(isset($this->oauth2AccessToken) && !empty($this->oauth2AccessToken)){
           return $this->oauth2AccessToken;
       }else{
           throw new SdkException("Can't get OAuth 2 Access Token Object. It is not set yet.");
       }
    }
public function getAccessToken(){
       if(isset($this->oauth2AccessToken) && !empty($this->oauth2AccessToken)){
           return $this->oauth2AccessToken;
       }else{
           throw new SdkException("Can't get OAuth 2 Access Token Object. It is not set yet.");
       }
    }
Return the OAuth 2 Access Token Obj from the login helper.
@return OAuth2AccessToken   The OAuth 2 Access Token object