// NOTE: Used to use for the first argument the following,
// but it seems to not work for relative file references:
// new URL("file", null, _directory.getAbsolutePath()
Configuration configuration = getConfiguration();
Tableau newAutomatonTableau = configuration.openModel(url,
url, url.toExternalForm());
// compose the two interface automata and show result
InterfaceAutomaton model1 = (InterfaceAutomaton) getFrame()
.getModel();