sinterface G22MasterStuff {
  void openDatabase(File dir);
  void closeDatabase(File dir);
  void switchToDatabase(File dir);
  Cl<File> openConceptDirs();
  G22MasterStuff onLoadedDBsChange(Runnable r);
  G22MasterStuff removeLoadedDBsChangeListener(Runnable r);
  IF1<S, Class> makeClassFinder();
}