GetCategoryFeaturesRequestType req = new GetCategoryFeaturesRequestType();
//we only need 'UpdateTime' field
//req.setOutputSelector(new String[]{"UpdateTime"});
//workaround, use CategoryVersion instead of UpdateTime here
req.setOutputSelector(new String[]{"CategoryVersion"});
api.execute(req);
GetCategoryFeaturesResponseType resp = (GetCategoryFeaturesResponseType) api.execute(req);
// Date date = resp.getUpdateTime().getTime();
// SimpleDateFormat df = new SimpleDateFormat("yyyy_MM_dd_hh_mm_ss");
// String time = df.format(date);
return resp.getCategoryVersion();