/**
  * Store a Drawing under a given name. If the file name does not have the correct file extension,
  * then the file extension is added.
  *
  * @param fileName file name of the Drawing under which it should be stored
  * @param saveDrawing drawing to be saved
  * @return file name with correct file extension
  */
 public String store(String fileName, Drawing saveDrawing) throws IOException {
   FileOutputStream stream = new FileOutputStream(adjustFileName(fileName));
   StorableOutput output = new StorableOutput(stream);
   output.writeStorable(saveDrawing);
   output.close();
   return adjustFileName(fileName);
 }
 public void write(StorableOutput dw) {
   super.write(dw);
   dw.writeStorable(getStartConnector());
   dw.writeStorable(getEndConnector());
 }