Question

I’m trying to handle a ViewExpiredException exception on an ajax call using primefaces 2.2.1 on glassfish 3.1. I have an ajaxStatus like this:

  <p:ajaxStatus id="ajaxStatus"  
                onstart="startAjaxDisplay()" 
                onerror="ajaxErrorHandler()" 
                oncomplete="endAjaxDisplay()"/> 

The onstart and oncomplete get called as expected. I know the ajaxErrorHandler() works because I put it in oncomplete instead and it got called. All it’s doing right now is popping up an alert(). I set up my test and the response from the server looks like this:

<?xml version="1.0" encoding="UTF-8"?>
<partial-response>
  <error>
    <error-name>class javax.faces.application.ViewExpiredException</error-name>
    <error-message><![CDATA[viewId:/index.xhtml - View /index.xhtml could not be restored.]]></error-message>
  </error>
  <changes>
    <extension primefacesCallbackParam="validationFailed">{"validationFailed":false}</extension>
  </changes>
</partial-response>

That’s all as expected except the onerror just doesn’t get called. Am I misunderstanding how this is supposed to work?

Answer 1

The onerror handler will be not called, because ViewExpiredException is not an AJAX error, but a JSF during the construction of the view that is already expired (the session expired).
PrimeFaces ajax component not handle this situation as an error.

In my solution (JSF2+PrimeFaces3) I investigate the ajax response from the server and search for an JSF error message. See the most simple example below:

<h:head>
    <title>Facelet Title</title>
    <script language="javasript" type="text/javascript">
        function handleAjaxRequest(xhr, status, args){
            var xmlDoc = xhr.responseXML;
            errorNodes = xmlDoc.getElementsByTagName('error-name');
            if (errorNodes.length == 0) return;
            errorName = errorNodes[0].childNodes[0].nodeValue;
            switch (errorName) {
                case 'class javax.faces.application.ViewExpiredException': 
                    alert ('Session expired, redirecting to login page!');

                    window.location.href = 'login.xhtml';
                break;
            }
        }    
    </script>
</h:head>

<h:body>
    <h:form id="frmText">
        Enter the value: <p:inputText value="#{bean.text}" />
        <p:commandButton value="Enter" update="frmText" 
                         oncomplete="handleAjaxRequest(xhr, status, args);"/>
        <p:separator />
        The entered text is: <h:outputText value="#{bean.text}" style="font-weight: 900"/>
    </h:form>
</h:body>