code: private void invokeTokenRequest(String grantCode) {
  
          AuthorizationRequestManager.RequestOptions options = new AuthorizationRequestManager.RequestOptions();
  
          options.parameters = createTokenRequestParams(grantCode);
          options.headers = createTokenRequestHeaders(grantCode);
          addSessionIdHeader(options.headers);
          options.requestMethod = Request.POST;
  
          InnerAuthorizationResponseListener listener = new InnerAuthorizationResponseListener() {
              @Override
              public void handleAuthorizationSuccessResponse(Response response) throws Exception {
                  saveTokenFromResponse(response);
                  handleAuthorizationSuccess(response);
              }
          };
  
          authorizationRequestSend(null, "token", options, listener);
      }
docs: Invoke request to get token, the result of the response should be a valid token
  @param grantCode grant code that will be used during the request