Java: Best way to work with Locales in Swing (with change at Runntime)?

Question

(Already posted here: http://stackoverflow.com/q/11298080/1469540)

I thought about the best way to implement localisation with runtime in Swing. Currently I solve the problem like that:

JMenu menuData = new JMenu("Data");
    menuData.setName("mainframe.menu.data"); // property key
    localeChangedListener.add(menuData);

The LocaleChangedListener:

public class SwingLocaleChangedListener implements LocaleChangedListener {

private ArrayList<AbstractButton>   abstractButtons;

@Override
public void localeChanged(ResourceBundle rb) {
    logger.info("Locale changed to '" + rb.getLocale() + "'");
    for (AbstractButton b : abstractButtons) {
        b.setText(rb.getString(b.getName()));
        b.setComponentOrientation(ComponentOrientation.getOrientation(rb.getLocale())); //EDIT: Line added
    }

}

public boolean add(AbstractButton b) {
    initAbstractButtons();
    return abstractButtons.add(b);
}

private void initAbstractButtons() {
    if (abstractButtons == null) {
        this.abstractButtons = new ArrayList<AbstractButton>();
    }
}

}

And the registration of the Listener:

public class GuiBundleManager {

private String                  filePrefix  = "language.lang";
private ResourceBundle          rb         = null;
private LocaleChangedListener   listener    = null;

private static GuiBundleManager instance    = null;

private GuiBundleManager() { 
    setLocale(Locale.getDefault());
}

public String getString(String key) {
    return rb.getString(key);
}

public String[] getStringArray(String key) {
    return rb.getStringArray(key);
}

public Locale getLocale() {
    return rb.getLocale();
}

public void setLocale(Locale l) {
    rb = ResourceBundle.getBundle(filePrefix, l);
    if (listener != null) {
        listener.localeChanged(rb);
    }

}

public LocaleChangedListener getLocaleChangedListener() {
    return listener;
}

public void setLocaleChangedListener(LocaleChangedListener listener) {
    this.listener = listener;
    if (listener != null) {
        listener.localeChanged(rb);
    }
}

public static GuiBundleManager get() {
    if (instance == null) {
        instance = new GuiBundleManager();
    }
    return instance;
}
}

. . An other way I'm thinking of is using Component.setLocale() combined with an PropertyChangedListener:

public abstract class GUIComponentFactory {

public JLabel createLocalisedJLabel(final String key) {
    final JLabel label = new JLabel(GuiBundleManager.get().getString(key));
    label.addPropertyChangeListener("locale", new PropertyChangeListener() {

        @Override
        public void propertyChange(PropertyChangeEvent e) {
            label.setText(GuiBundleManager.get().getString(key));
            label.setComponentOrientation(ComponentOrientation.getOrientation(e.getNewValue())); //Edit: Line added
            for(Component c : getComponents()){
                c.setLocale(e.getNewValue());
            }
        }
    });
            return label;

}
.
.
.

}

Maybe you have a better solution

Answer 1

Consider applyComponentOrientation(), which recursively "Sets the ComponentOrientation property of this component and all components contained within it." Examples may be found here.

Answer 2

Whatever approach you finally decide upon: you don't have to handle the resourceBundles yourself. Instead, add them to the UIManager and query that for the localized values:

// edited: it's the defaults which take the bundle, my bad I didn't check core api
// SwingX has a UIManagerExt which takes it directly :-)
UIManager.getDefaults().addResourceBundle("com.xypackage.resources.MyBundle");
...
label.setText(UIManager.get(key, label.getLocale());

There used to be (didn't check if it's fixed) a bug which prevented this to work reliably in webstartables.