jsf params conservation

I tried to create a an link - image that changes the language of a page. But I encountered an issue开发者_如何学运维, that the GET url params got lost after the ajax call, so not only the language changed, but also the content changed because of no params. The solution I found is to write down every single param that I use accross the whole website and try put it into the command link. But, I hope that this is not a neatest solution. Can you think of one?

<h:commandLink id="language" actionListener="#{userBean.changeLanguage}">
 <f:param name="itemId" value="#{param.itemId}" />
 <f:param name="categoryId" value="#{param.categoryId}" />
 <f:ajax render="@all" />
</h:commandLink>

Yes, my site is not a huge one, there are just two params, but I want to learn for future.

Make them properties of a @ViewScoped bean.

@ManagedBean
@ViewScoped
public class Bean {

    @ManagedProperty(value="#{param.itemId}")
    private Long itemId;

    @ManagedProperty(value="#{param.categoryId}")
    private Long categoryId;

    // ...
}

And they'll be there as long as the view-to-view conversation lasts.