HFM v.11.1.2.4, Java API "getApplicationEnabledStatus" throws HFMException

HFM v.11.1.2.4, use Java API to communicate with HFM.

I am trying to get HFM application mode (Admin/User):

...

    try {

String hfm_cluster = "CLUSTER";

       String application = "APPLICATION";

       String username = "user1";

       String password = "psw1";

       Map context = new HashMap(5);

       CSSSystem system = CSSSystem.getInstance(context, "HYPERION_HOME");

       CSSAPIIF css = system.getCSSAPI();

       CSSUserIF user = css.authenticate(context, username, password);

       String ssoToken = user.getToken();   

SessionOM sessionOM = new SessionOM();

String server = sessionOM.getAvailableServer(ssoToken, hfm_cluster);  

HsxRequestContext hsxRequestContext = new HsxRequestContext(null, ssoToken, null, null);

       JHsxClient client = JHsxClient.getInstance();

     APPLICATION_ENABLED_STATUS applicationEnabledStatus = 

client.getApplicationEnabledStatus(hsxRequestContext, ssoToken, hfm_cluster, server, hfm_application);

    } catch (HFMException e) {

     ...

    }

All parameters for the function getApplicationEnabledStatus are set - non-null.