JSF: Cannot catch ViewExpiredException
- by ifischer
I'm developing a JSF 2.0 application on Glassfish v3 and i'm trying to handle the ViewExpiredException. But whatever i do, i always get a Glassfish error report instead of my own error page.
To simulate the occurrence of the VEE, i inserted the following function into my backing bean, which fires the VEE. I'm triggering this function from my JSF page through a commandLink.
The Code:
@Named
public class PersonHome {
(...)
public void throwVEE() {
throw new ViewExpiredException();
}
}
At first i tried it by simply adding an error-page to my web.xml:
<error-page>
<exception-type>javax.faces.application.ViewExpiredException</exception-type>
<location>/error.xhtml</location>
</error-page>
But this doesn't work, i'm not redirected to error but i'm shown the Glassfish errorpage, which shows a HTTP Status 500 page with the following content:
description:The server encountered an internal error () that prevented it from fulfilling this request.
exception: javax.servlet.ServletException: javax.faces.application.ViewExpiredException
root cause: javax.faces.el.EvaluationException:javax.faces.application.ViewExpiredException
root cause:javax.faces.application.ViewExpiredException
Next thing i tried was to write ExceptionHandlerFactory and a CustomExceptionHandler, as described in JavaServerFaces 2.0 - The Complete Reference. So i inserted the following tag into faces-config.xml:
<factory>
<exception-handler-factory>
exceptions.ExceptionHandlerFactory
</exception-handler-factory>
</factory>
And added these classes:
The factory:
package exceptions;
import javax.faces.context.ExceptionHandler;
public class ExceptionHandlerFactory extends javax.faces.context.ExceptionHandlerFactory {
private javax.faces.context.ExceptionHandlerFactory parent;
public ExceptionHandlerFactory(javax.faces.context.ExceptionHandlerFactory parent) {
this.parent = parent;
}
@Override
public ExceptionHandler getExceptionHandler() {
ExceptionHandler result = parent.getExceptionHandler();
result = new CustomExceptionHandler(result);
return result;
}
}
The custom exception handler:
package exceptions;
import java.util.Iterator;
import javax.faces.FacesException;
import javax.faces.application.NavigationHandler;
import javax.faces.application.ViewExpiredException;
import javax.faces.context.ExceptionHandler;
import javax.faces.context.ExceptionHandlerWrapper;
import javax.faces.context.FacesContext;
import javax.faces.event.ExceptionQueuedEvent;
import javax.faces.event.ExceptionQueuedEventContext;
class CustomExceptionHandler extends ExceptionHandlerWrapper {
private ExceptionHandler parent;
public CustomExceptionHandler(ExceptionHandler parent) {
this.parent = parent;
}
@Override
public ExceptionHandler getWrapped() {
return this.parent;
}
@Override
public void handle() throws FacesException {
for (Iterator<ExceptionQueuedEvent> i = getUnhandledExceptionQueuedEvents().iterator(); i.hasNext();) {
ExceptionQueuedEvent event = i.next();
System.out.println("Iterating over ExceptionQueuedEvents. Current:" + event.toString());
ExceptionQueuedEventContext context = (ExceptionQueuedEventContext) event.getSource();
Throwable t = context.getException();
if (t instanceof ViewExpiredException) {
ViewExpiredException vee = (ViewExpiredException) t;
FacesContext fc = FacesContext.getCurrentInstance();
NavigationHandler nav =
fc.getApplication().getNavigationHandler();
try {
// Push some useful stuff to the flash scope for
// use in the page
fc.getExternalContext().getFlash().put("expiredViewId", vee.getViewId());
nav.handleNavigation(fc, null, "/login?faces-redirect=true");
fc.renderResponse();
} finally {
i.remove();
}
}
}
// At this point, the queue will not contain any ViewExpiredEvents.
// Therefore, let the parent handle them.
getWrapped().handle();
}
}
But STILL i'm NOT redirected to my error page - i'm getting the same HTTP 500 error like above.
What am i doing wrong, what could be missing in my implementation so that the exception is handled correctly?
