src/Core/OAuth/OAuth2/OAuth2LoginHelper.php
private function checkIfEmptyValueReturned($tokenExpiresTime, $refreshToken, $refreshTokenExpiresTime, $accessToken){
      if(empty($tokenExpiresTime)){
        throw new SdkException("Error Retrieve RefreshToken from Response. Token Expires In Time is Empty.");
      }

      if(empty($refreshToken)){
        throw new SdkException("Error Retrieve RefreshToken from Response. Refresh Token is Empty.");
      }

      if(empty($refreshTokenExpiresTime)){
        throw new SdkException("Error Retrieve RefreshToken from Response. Refresh Token Expires Time is Empty.");
      }

      if(empty($accessToken)){
        throw new SdkException("Error Retrieve RefreshToken from Response. Access Token is Empty.");
      }
    }
private function checkIfEmptyValueReturned($tokenExpiresTime, $refreshToken, $refreshTokenExpiresTime, $accessToken){
      if(empty($tokenExpiresTime)){
        throw new SdkException("Error Retrieve RefreshToken from Response. Token Expires In Time is Empty.");
      }

      if(empty($refreshToken)){
        throw new SdkException("Error Retrieve RefreshToken from Response. Refresh Token is Empty.");
      }

      if(empty($refreshTokenExpiresTime)){
        throw new SdkException("Error Retrieve RefreshToken from Response. Refresh Token Expires Time is Empty.");
      }

      if(empty($accessToken)){
        throw new SdkException("Error Retrieve RefreshToken from Response. Access Token is Empty.");
      }
    }
A helper function to check Null value
@param String $tokenExpiresTime            access token expires time
@param String $refreshToken                Refreh Token
@param String $refreshTokenExpiresTime     refresh token expires time
@param String $accessToken                 accessToken