web.xml错误页面不起作用，为什么？

Question

I'm running out of ideas by now, and don't know what else to try. The point is not even one error-page is working, I just would like to know, what am I doing wrong?, here is the code:

<error-page>
    <exception-type>javax.faces.application.ViewExpiredException</exception-type>
    <location>/sessionexpired.xhtml</location>
</error-page>
<error-page>
    <error-code>500</error-code>
    <location>/500.xhtml</location>
</error-page>

When having this code in my web.xml I get this message:

XML read error: no element found

What this message means? how can I solve this? Thanks.

BTW, I have also tried to use filters to handle the ViewExpiredException , then it works the first time when I send the POST message and redirects to the sessionexpired.xhtml. But if I click backward and then make the POST call again BAM! I get again the ViewExpiredException .

UPDATE 30-NOV-2011 --[ALTERNATE SOLUTION]-------------------------------------

After a while I found that in order to make it work you have to specify the loation to .html or .jsp files , so it would end up being:

<error-page>
    <exception-type>javax.faces.application.ViewExpiredException</exception-type>
    <location>/sessionexpired.html</location>
</error-page>
<error-page>
    <error-code>500</error-code>
    <location>/500.jsp</location>
</error-page>

Answer 1

Well, for those that are strugling with this issue using Glassfish 3.1, you can handle that problem by following this article to the letter, even thought I changed at the end to use sendRedirect() instead of the JSF navigator to render the sessionexpired.xhtml file, but that's your choice, it works fine. Here you go:

http://weblogs.java.net/blog/edburns/archive/2009/09/03/dealing-gracefully-viewexpiredexception-jsf2

Answer 2

After you change the web.xml, have you do the ear or war redeployment? Some of the application server might cache the old copy of web.xml if you directly go to server to modify the file. Hopefully it can work. :)

Answer 3

May be some problem try this may it helps..
<error-page> tag come after the <servlet-mapping> element.

<web-app>
...
<servlet>
 ...
  </servlet>
  <servlet-mapping>
    .....
  </servlet-mapping>
  ...
  <welcome-file-list>
  ...
   </welcome-file-list>
  <error-page>
    <error-code>404</error-code>
    <location>/errorpages/html404.html</location>
  </error-page>
 <taglib>
 ...
 </taglib>
 ...
</web-app>

Answer 4

When having this code in my web.xml I get this message:

  XML read error: no element found 

As per the comments it turns out that you're seeing this in the browser instead of the expected error page. I initially interpreted it being mentiond by your IDE/editor due to a syntax error in web.xml . Your question wasn't entirely clear on that.

Well, the solution to that is easy: make sure that the <location> of the <error-page> matches the URL pattern of the FacesServlet . Easiest would be to just map the FacesServlet on an URL pattern of *.xhtml .

---

BTW, I have also tried to use filters to handle the ViewExpiredException, then it works the first time when I send the POST message and redirects to the sessionexpired.xhtml. But if I click backward and then make the POST call again BAM! I get again the ViewExpiredException.

This is just caused by the page being requested from the browser cache instead of straight from the server. See also this answer for a concrete solution: browser back + viewscope beans .