code: private void refreshStreamPosition() throws IOException {
      if (currentEditLogInputStreamPosition != -1) {
        // stream was reopened
        currentEditLogInputStream.refresh(currentEditLogInputStreamPosition,
            mostRecentlyReadTransactionTxId);
      } else {
        // freshly opened stream
        currentEditLogInputStreamPosition = currentEditLogInputStream.getPosition();
      }
    }
docs: Called to refresh the position in the current input stream to the last
  ACK'd one.
  
  @throws IOException
  if a fatal error occurred.