application scoped bean's view is not updated

问题

I have a variable inside an application scoped bean. A user can trigger an update of this variable through a method call. Now the problem is that the user doesn't get an updated view of this variable after refreshing the jsf page. If have tested if the variable is updated properly and it is, so the method for updating is working correctly. Are variables inside an application scoped bean declared as final or what is the problem here?

回答1:

That can happen if you used the wrong combination of annotations. E.g.

import javax.enterprise.context.ApplicationScoped;
import javax.faces.bean.ManagedBean;

@ManagedBean
@ApplicationScoped
public class App {}

Here, the scope annotation is from CDI and the bean management annotation is from JSF. JSF doesn't recognize CDI scope annotations and hence defaults to @NoneScoped. I.e. the bean is reconstructed on every single EL #{app} evaluation. This explains the symptoms you're seeing.

You'd need to fix the scope annotation to be from JSF as well.

import javax.faces.bean.ApplicationScoped;
import javax.faces.bean.ManagedBean;

@ManagedBean
@ApplicationScoped
public class App {}

The CDI scope annotations can only be used in combination with the CDI bean management annotation @Named.

来源：https://stackoverflow.com/questions/13069125/application-scoped-beans-view-is-not-updated