Silence FullAjaxExceptionHandler

Question

So after being confronted with the dreaded javax.faces.application.ViewExpiredException, I had to go look around the internet to find the proper solution. Fortunately, the solutions are readily available and I went ahead and adopted the OmniFaces FullAjaxExceptionHandler.

Enough said, as with pretty much everything from OmniFaces, it worked wonders. But, every time I have a view expiring I am getting :

SEVERE: WebModule[/myModule]FullAjaxExceptionHandler: An exception occurred during processing JSF ajax request. Error page '/WEB-INF/errorpages/test.xhtml' will be shown.
javax.faces.application.ViewExpiredException: viewId:/my/page.xhtml - View /my/page.xhtml could not be restored.
...

This is fine as it is handled as expected, but is there anyway to silence this exception from being printed to the server.log? This would crowd the log pretty quickly.

I am running :
Mojarra 2.1.23
PrimeFaces 4.0-SNAPSHOT
OmniFaces 1.6-SNAPSHOT-2013-07-01

on
Glassfish 3.1.2.2

Tavia

Answer 1

As per OmniFaces 1.6, you can extend it and override the method logException() as below to skip the stack trace for ViewExpiredException.

public class YourAjaxExceptionHandler extends FullAjaxExceptionHandler {

    public YourAjaxExceptionHandler(ExceptionHandler wrapped) {
        super(wrapped);
    }

    @Override
    protected void logException(FacesContext context, Throwable exception, String location, String message, Object... parameters) {
        if (exception instanceof ViewExpiredException) {
            // With exception==null, no trace will be logged.
            super.logException(context, null, location, message, parameters);
        }
        else {
            super.logException(context, exception, location, message, parameters);
        }
    }

}

Create a factory around it:

public class YourAjaxExceptionHandlerFactory extends ExceptionHandlerFactory {

    private ExceptionHandlerFactory wrapped;

    public YourAjaxExceptionHandlerFactory(ExceptionHandlerFactory wrapped) {
        this.wrapped = wrapped;
    }

    @Override
    public ExceptionHandler getExceptionHandler() {
        return new YourAjaxExceptionHandler(getWrapped().getExceptionHandler());
    }

    @Override
    public ExceptionHandlerFactory getWrapped() {
        return wrapped;
    }

}

In order to get this to run, register it as factory in faces-config.xml the usual way (don't forget to remove the original registration for FullAjaxExceptionHandlerFactory):

<factory>
    <exception-handler-factory>com.example.YourExceptionHandlerFactory</exception-handler-factory>
</factory>

Sandbag

@Sandbag a switch is missing in MyAjaxExceptionHandler#logException. This line needs to be inside the else: super.logException(context, exception, location, message, parameters);. Also, if I'm not mistaken the faces-config.xml <exception-handler-factory> needs to be com.example.MyAjaxExceptionHandlerFactory. – Marthena