How to handle session expiration and ViewExpiredException in JSF 2?

问题

Consider the following scenario. I am clicking the submit button of a JSF form, after the session has timed out(expired). The browser displays some exception message:

ViewExpiredException: view context could not be restored

What I want to do is, to automatically redirect to the homepage of the website after the session has expired. What is the mechanism to do this? Any help would be much appreciated.

回答1:

To handle the exception whenever the user invokes a synchronous POST request on a page while the HTTP session has been expired and the JSF view state saving method is set to server, add an <error-page> to the web.xml which catches the JSF ViewExpiredException and shows the home page.

<error-page>
    <exception-type>javax.faces.application.ViewExpiredException</exception-type>
    <location>/home.xhtml</location>
</error-page>

To handle the exception on asynchronous (ajax) requests as well, you need to implement a custom ExceptionHandler as answered in Session timeout and ViewExpiredException handling on JSF/PrimeFaces ajax request

See also:

• javax.faces.application.ViewExpiredException: View could not be restored

来源：https://stackoverflow.com/questions/4992526/how-to-handle-session-expiration-and-viewexpiredexception-in-jsf-2