When Managed Bean creates and property of the beans creates?

In our application we use jsf,we have to redirect the user to home page after their session will be expired.For that i need a path of the home page which i kept in my logout managed bean as a managed bean property.But after session expired if i try to access that it will arise null pointer exception(managed bean becomes null).Then i have decide to try alternative (i.e)create logout class manually and try to access the property, at that time the property which i wants to access is becom开发者_Go百科e null.How can i access that property? Please help me. Thanks in advance.

In addition to the previous answer:

You could use (in web.xml)

<error-page>
<exception-type>javax.faces.application.ViewExpiredException</exception-type>
<location>viewexpired.jsp</location>
</error-page>

Or Context Parameters instead of Session Attributes. See:

• http://tomcat.apache.org/tomcat-5.5-doc/config/context.html
• http://safebox.guisho.com/jsf-how-to-get-webxml-parameters

Or use (in faces-context.xml)

<managed-bean-scope>application</managed-bean-scope> 

for your bean, so it will stay independent from the session.

Correct way of doing this is declaring exception handler factory in faces-config.xml, then implementing the factory by subclassing javax.faces.context.ExceptionHandlerFactory, and then overriding handle() method in your implementation of javax.faces.context.ExceptionHandlerWrapper. There you should analyze the exception for the ViewExpiredException class and redirect to your view expired page in that case.