code: private byte[] getNextRow(byte[] row, long writePointer, int count) {
      Bytes.putLong(row, queueRowPrefix.length, writePointer);
      Bytes.putInt(row, queueRowPrefix.length + Longs.BYTES, count + 1);
      return row;
    }
docs: Get the next row based on the given write pointer and counter. It modifies the given row byte[] in place
  and returns it.