code: public long[] getLongs(int rowId, int count) {
      long[] res = new long[count];
      for (int i = 0; i < count; i++) {
        res[i] = getLong(rowId + i);
      }
      return res;
    }
docs: Gets long type values from [rowId, rowId + count). The return values for the null slots
  are undefined and can be anything.