public void readPreferences() {
		language = preferences.get("language", "en");
		setLookAndFeel(preferences.get("lookAndFeel",
				"javax.swing.plaf.nimbus.NimbusLookAndFeel"));
		if (preferences.get("solutionType",
				SolutionType.DETAILLED_SOLUTION.name()).compareTo(
				SolutionType.DETAILLED_SOLUTION.name()) == 0)
			setSolutionType(SolutionType.DETAILLED_SOLUTION);
		else
			setSolutionType(SolutionType.MINIMIZED_FUNCTION);
		maximazed = preferences.getBoolean("maximazed", false);
		height = preferences.getInt("height", 0);
		width = preferences.getInt("width", 0);
		Locale locale = new Locale(language);
		Locale.setDefault(locale);
		Tools.updateSwingResourceLanguage();
	}