Localized Accelorator Keys

Question

Hi folks,
I have a problem with localization and accelerator keys. I am developing a localized Swing GUI where a user can set his preffered Locale and then all texts are translated.... That's all no prob. The problem is, that in JMenus the accelerator keys for items are displayed not according to the set default locale (e.g., en-US) but are displayed according to the OS user.language (in my case de [German]). Hence, the accel. keys read, e.g., '*Strg-N*' instead of '*Ctrl-N*' as expected for default locale en.
This is just a display problem, the functionality / the keys work fine, of course.
I guess my prob is (somehow) related to the awt.properties. When invoking, e.g., KeyEvent.getKeyModifiersText(keyStroke.getModifiers() (which I assume is called for JMenuItems to display the acc keys) I get the modifier key as string in German. These properties are loaded on startup? according to the OS user language. If i change my user language (e.g., with the jvm switch -Duser.language=en) everything is fine. When changing this system property inside Java Code (e.g. in my main-method) the awt.properties are already loaded (somehow) with the OS user.language. Hence, this option doesn't work.
Has anybody an idea / workaround how I get these modifier keys displayed localized. Is there perhaps a way to change the awt-property on runtime or, at least, to set the values of these properties, e.g. AWT.control?
Thanks!

Answer 1

The solution would be to set the user language or the locale before the Toolkit class gets loaded. This would generally be VERY early in the startup sequence, say the first lines of your main method. Because as soon as you start using any GUI related classes such as JFrame, the Toolkit class will also get loaded.
In my first attempt to solve your problem it didn't work even though I set the locale on the FIRST line of my main method. The problem was that my test class itself extended from JFrame, so the JFrame class got loaded before the main method executed. And loading JFrame means also loading Component means loading Toolkit means the resources got loaded with the default VM user language.
See the Toolkit class, where you can find the following code (I put a break point on this line):
resources = ResourceBundle.getBundle("sun.awt.resources.awt", CoreResourceBundleControl.getRBControlInstance());Find below a running example which solves your problem:
import java.awt.BorderLayout;
import java.awt.event.ActionEvent;
import java.util.Locale;
import javax.swing.AbstractAction;
import javax.swing.Action;
import javax.swing.JFrame;
import javax.swing.JMenu;
import javax.swing.JMenuBar;
import javax.swing.JMenuItem;
import javax.swing.JOptionPane;
import javax.swing.KeyStroke;
import javax.swing.SwingUtilities;
public class Accelerators {
    static void createAndShowGui() {
        JMenuBar bar = new JMenuBar();
        JMenu menu = new JMenu("File");
        bar.add(menu);
        menu.add(new JMenuItem(new AbstractAction() {
                putValue(Action.NAME, "Save");
                putValue(Action.ACCELERATOR_KEY, KeyStroke
                        .getKeyStroke("ctrl S"));
            public void actionPerformed(ActionEvent e) {
                JOptionPane
                        .showConfirmDialog(
                                null,
                                "Notice language of dialog caption & buttons.\nThese also depend on the user.language");
        JFrame f = new JFrame("Accelerators");
        f.getContentPane().add(bar, BorderLayout.NORTH);
        f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        f.setLocationRelativeTo(null);
        f.setSize(300, 300);
        f.setVisible(true);
    public static void main(String[] args) {
        // Locale.setDefault(Locale.US);
        Locale.setDefault(Locale.GERMAN);
        // or:
        // System.setProperty("user.language", "en");
        // System.setProperty("user.language", "de");
        SwingUtilities.invokeLater(new Runnable() {
            public void run() {
                createAndShowGui();
}