serialization problems -whether it is a serious matter?

[Jan Crownman]

Hi

I'm using Wicket and Maven. Both are relatively new things to me. I'm currently working on a localization, I need a multilingual page.

When I'm building my code I get a warning:
WARN - AbstractPropertyModel - It is not a good idea to reference the Session instance in models directly as it may lead to serialization problems. If you need to access a property of the session via the model use the page instance as the model object and 'session.attribute' as the path.

I'm calling a class DropDownLocale like this:
PropertyModel<Locale> model = new PropertyModel<Locale>(getSession(), "locale");
DropDownLocale selectLanguage = new DropDownLocale("selectLanguage", model, supportedLanguages);
add(selectLanguage);

Does anybody know what I'm doing wrong?

[Wouter Oet]

Moved to Other Application Frameworks.

[Jan Crownman]

I solved this:

1. LocaleDropDown class

@SuppressWarnings("rawtypes")
public class LocaleDropDown extends DropDownChoice {

	private static final long serialVersionUID = 1L;
	private class LocaleRenderer extends ChoiceRenderer {
		
		private static final long serialVersionUID = 1L;

	@Override public String getDisplayValue(Object locale) {
		return ((Locale) locale).getDisplayName(getLocale());
   	   }
}

@SuppressWarnings({ "unchecked", "serial" })
public LocaleDropDown(String id, List<Locale> supportedLocales) { 
	super(id, supportedLocales); 
	setChoiceRenderer(new LocaleRenderer()); 
	setModel(new IModel() {

	    public Object getObject() { 
		return getSession().getLocale();
	    }

	public void setObject(Object object) { 
	   getSession().setLocale((Locale) object);
	}
	public void detach() {
	} 
	});
}

	@Override 
	protected boolean wantOnSelectionChangedNotifications() {
	return true;
	}
    
}

2. Java call on HomePage.java

List<Locale> supportedLanguages = new ArrayList<Locale>();
  fiLocale = new Locale("fi", "Finland");
  enLocale = new Locale("en", "English");
  supportedLanguages.add(fiLocale);
  supportedLanguages.add(enLocale); 
  add(new LocaleDropDown("localeSelect", supportedLanguages));

3. Html

<select wicket:id="localeSelect"></select>