Apps NetworkStatsManager querySummaryForDevice strange results

[Mauro Esposito]

I want to get the mobile data consumption for a given range of date (1, 2, 5, 10 or 15 minutes) with the querySummaryForDevice method of NetworkStatsManager.

This is my code:

public static long getTotalTrafficInRange(Context context, Date fromDate, Date toDate) throws UsageStatsNotActiveException, NoPermissionException
{
   boolean usageStatsActive = doIHavePermission(context);

   if (!usageStatsActive) {
       throw new UsageStatsNotActiveException(context);
   }

   long total = 0;

   TelephonyManager tele = (TelephonyManager) context.getSystemService(Context.TELEPHONY_SERVICE);
   if (ActivityCompat.checkSelfPermission(context, Manifest.permission.READ_PHONE_STATE) != PackageManager.PERMISSION_GRANTED) {
       throw new NoPermissionException(Manifest.permission.READ_PHONE_STATE);
   }
   String actualSubscriberId = tele.getSubscriberId();

   NetworkStatsManager networkStatsManager = (NetworkStatsManager) context.getSystemService(Context.NETWORK_STATS_SERVICE);

   Date from = ConvertDateToCalendar(fromDate);
   Date to = ConvertDateToCalendar(toDate);

   //Total
   NetworkStats.Bucket bucket;
   try {
       bucket = networkStatsManager.querySummaryForDevice(ConnectivityManager.TYPE_MOBILE, actualSubscriberId, from.getTime(), to.getTime());

       if(bucket != null){
           total = (bucket.getRxBytes() + bucket.getTxBytes());
       }

   } catch (RemoteException e) {
       e.printStackTrace();
   }

   return total;
}

I tried to convert my date in calendar and back again in Date with this code:

public static Date ConvertDateToCalendar(Date date)
{
   Calendar fromDateCalendar = Calendar.getInstance();
   fromDateCalendar.setTime(date);

   Calendar calendar = Calendar.getInstance();
   calendar.set(Calendar.YEAR, fromDateCalendar.get(Calendar.YEAR));
   calendar.set(Calendar.MONTH, fromDateCalendar.get(Calendar.MONTH));
   calendar.set(Calendar.DAY_OF_MONTH, fromDateCalendar.get(Calendar.DAY_OF_MONTH));
   calendar.set(Calendar.HOUR_OF_DAY, fromDateCalendar.get(Calendar.HOUR_OF_DAY));
   calendar.set(Calendar.MINUTE, fromDateCalendar.get(Calendar.MINUTE));
   calendar.set(Calendar.SECOND, fromDateCalendar.get(Calendar.SECOND));
   calendar.set(Calendar.MILLISECOND, fromDateCalendar.get(Calendar.MILLISECOND));

   return calendar.getTime();
}

This is the fromDate and toDate:

//this date is new Date() minus 1,2,3,5,10 or 15 minutes, not more then this values
   fromDate = new Date(PersistentHelper.getLastDateUsedForCalculateData(context));

   //Calculate toDate
   Calendar calendar = Calendar.getInstance();
   calendar.setTime(new Date());
   if(!userChangeDateManually || !userChangeZone) {
       calendar.set(Calendar.SECOND, 0);
   }
   calendar.add(Calendar.MILLISECOND, -1);

   toDateWS = calendar.getTime();

But totalBytes returned by getTotalTrafficInRange it's not real. If I have my phone in WIFI for 1 hour and then call my function with fromDate 15 minute ago, it return a very long value and not 0 as expected.

There is a limit for the range date of the querySummaryForDevice method of NetworkStatsManager? No clue found in documentation.

Anyone notice this weird behaviour?