int count = 20;
  double all = 0.0;
  for (int i = 0; i < count; ++i) {
   long begin = Calendar.getInstance().getTimeInMillis();
   dao.findAll();
   long end = Calendar.getInstance().getTimeInMillis();
   long diff = end - begin;
   all += diff;
   System.err.println("Iteration #" + (i + 1) + " " + diff + " ms");
  }
  double middle = all / (double) count;
  System.err.println("Average time is " + middle + " ms");