CODEWITHSUNDEEP
jsf-2managed-beanphaselistener
Matthew Oakley
Matthew Oakley

Reputation: 527

Cannot reference ViewScoped Managed bean from PhaseListener in JSF 2.1 app

I've tried every solution from a couple dozen google searches: getRequestMap, ElResolver, evaluateExpressionGet and so on. Nothing, absolutely nothing, works. I get null every time. Here is the relevant code:

    @ManagedBean(name="readerBean")
    @ViewScoped
    public class ReaderBean implements Serializable {...

And in the PhaseListener:

     public void beforePhase(PhaseEvent event) {

    if (event.getPhaseId() == PhaseId.RESTORE_VIEW) {

            ReaderBean r = null; //The Managed Bean
            try {
                FacesContext fctx = FacesContext.getCurrentInstance();
                r=(ReaderBean) fctx.getExternalContext().getRequestMap().get("readerBean");
                r=(ReaderBean) fctx.getELContext().getELResolver().getValue(fctx.getELContext(), null, "readerBean");
                r=(ReaderBean) fctx.getApplication().getExpressionFactory().createValueExpression(fctx.getELContext(), "#{readerBean}", ReaderBean.class).getValue(fctx.getELContext());
                r=(ReaderBean) fctx.getApplication().evaluateExpressionGet(fctx, "#{readerBean}", ReaderBean.class);

Nothing works!!!

Upvotes: 2

Views: 926

Answers (1)

BalusC
BalusC

Reputation: 1108782

As to the request map approach, it fails because a view scoped bean is not stored in the request scope. It's instead stored in the view scope. As to the other approaches, they fail because the view scoped bean is stored in the view and thus only available after the view has been restored. However, you're trying to get it before the view has been restored. This is a chicken-egg problem.

You need to revise your approach. Perhaps the bean needs to be a request scoped one? Perhaps the logic needs to be executed at a different phase? Perhaps the logic needs to be performed in the bean itself instead? Etc.

As the concrete functional requirement for which you thought that this is the right solution is unmentioned in the question, I can't point you in the right direction.

Upvotes: 2

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