code: @Override
    public void close () throws IOException
    {
      if (in != null)
      {
        in.close ();
        in = null;
        m_aBuf = null;
      }
    }
docs: Closes this input stream and releases any system resources associated with
  the stream. Once the stream has been closed, further read(), unread(),
  available(), reset(), or skip() invocations will throw an IOException.
  Closing a previously closed stream has no effect.
  
  @exception IOException
  if an I/O error occurs.