code: public OutlookMessage parseMsg(@Nonnull final InputStream msgFileStream)
  			throws IOException {
  		// the .msg file, like a file system, contains directories and documents within this directories
  		// we now gain access to the root node and recursively go through the complete 'filesystem'.
  		final OutlookMessage msg = new OutlookMessage(rtf2htmlConverter);
  		try {
  			checkDirectoryEntry(new POIFSFileSystem(msgFileStream).getRoot(), msg);
  		} finally {
  			msgFileStream.close();
  		}
  		convertHeaders(msg);
  		return msg;
  	}
docs: Parses a .msg file provided by an input stream.
  
  @param msgFileStream The .msg file as a InputStream.
  @return A {@link OutlookMessage} object representing the .msg file.
  @throws IOException Thrown if the file could not be loaded or parsed.