private static void preInterface() {
        Logger.getLogger(BookNaviger.class.getName()).entering(BookNaviger.class.getName(), "preInterface");
        try {
            if (OSBasics.isMac()) {
                MacOSXApplicationAdapter.setMacInterfaceAndCommands();
            }
            try {
                UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
            } catch (ClassNotFoundException | InstantiationException | IllegalAccessException | UnsupportedLookAndFeelException ex) {
                Logger.getLogger(BookNaviger.class.getName()).log(Level.SEVERE, "Couldn't set the system LookAndFeel", ex);
            }
            String languageWanted = PropertiesManager.getInstance().getKey("language");
            if (languageWanted != null) {
                switch (languageWanted) {
                    case "fr":
                        Locale.setDefault(Locale.FRENCH);
                        Logger.getLogger(BookNaviger.class.getName()).log(Level.INFO, "Setting language to French");
                        break;
                    case "en":
                        Locale.setDefault(Locale.ENGLISH);
                        Logger.getLogger(BookNaviger.class.getName()).log(Level.INFO, "Setting language to English");
                        break;
                }
            }
        } catch (Exception ex) {
            Logger.getLogger(BookNaviger.class.getName()).log(Level.SEVERE, "Unknown exception", ex);
            new InfoInterface(InfoInterface.InfoLevel.ERROR, "unknown");
        }
        Logger.getLogger(BookNaviger.class.getName()).exiting(BookNaviger.class.getName(), "preInterface");
    }