Package will not be available at compile time in Java 9. Use java.awt.Desktop instead. See JEP 272 'Platform-Specific Desktop Features': http://openjdk.java.net/jeps/272
public static void StartStudioMode() { Application app = Application.getApplication(); app.addAboutMenuItem(); app.setEnabledAboutMenu(true); if(app.isPreferencesMenuItemPresent()) app.removePreferencesMenuItem(); // no prefs from here app.addApplicationListener(new MacApplicationListener()); }