Primefaces ExceptionHandler not working as in the showcase

Question

I've tried the new ExceptionHandler tag in primefaces but it seems that I'm missing something with this tag.

Basically my code is the same as in http://www.primefaces.org/showcase/ui/misc/exceptionHandler.xhtml , the problem is that adding this tag doesn't change anything I'm not getting any thing on client side. The standard js API is not working either with prime buttons:

jsf.ajax.addOnError(function(data) {alert('Error');})

The only difference I've noticed between my running app and Primefaces showcase is that the ajax response I get is different from the showcase's one:

My response:

showcases's response

here is the code

<h:form>
<h3 style="margin-top:0">AJAX</h3>
<p:commandButton actionListener="#{exceptionHandlerView.throwViewExpiredException}"
                 ajax="true"
                 value="Throw ViewExpiredException!" />
<p:commandButton actionListener="#{exceptionHandlerView.throwNullPointerException}"
                 ajax="true"
                 value="Throw NullPointerException!" />
<p:commandButton actionListener="#{exceptionHandlerView.throwWrappedIllegalStateException}"
                 ajax="true"
                 value="Throw IllegalStateException!" />

<h3>Non-AJAX</h3>
<p:commandButton actionListener="#{exceptionHandlerView.throwViewExpiredException}"
                 ajax="false"
                 value="Throw ViewExpiredException!" />
<p:commandButton actionListener="#{exceptionHandlerView.throwNullPointerException}"
                 ajax="false"
                 value="Throw NullPointerException!" />


<p:ajaxExceptionHandler type="javax.faces.application.ViewExpiredException"
                        update="exceptionDialog"
                        onexception="PF('exceptionDialog').show();" />

<p:ajaxExceptionHandler type="java.lang.NullPointerException"
                        update="exceptionDialog"
                        onexception="PF('exceptionDialog').show();" />

<p:dialog id="exceptionDialog" header="Exception '#{pfExceptionHandler.type}' occured!" widgetVar="exceptionDialog"
          height="500px">
    Message: #{pfExceptionHandler.message} <br/>
    StackTrace: <h:outputText value="#{pfExceptionHandler.formattedStackTrace}" escape="false" /> <br />

    <p:button onclick="document.location.href = document.location.href;"
              value="Reload!"
              rendered="#{pfExceptionHandler.type == 'javax.faces.application.ViewExpiredException'}" />
</p:dialog>

package org.primefaces.showcase.view.misc;


import javax.faces.FacesException;
import javax.faces.application.ViewExpiredException;
import javax.faces.bean.ManagedBean;
import javax.faces.bean.RequestScoped;
import javax.faces.context.FacesContext;

@ManagedBean
@RequestScoped
public class ExceptionHandlerView {

    public void throwNullPointerException() {
        throw new NullPointerException("A NullPointerException!");
    }

    public void throwWrappedIllegalStateException() {
        Throwable t = new IllegalStateException("A wrapped IllegalStateException!");
        throw new FacesException(t);
    }

    public void throwViewExpiredException() {
        throw new ViewExpiredException("A ViewExpiredException!",
                FacesContext.getCurrentInstance().getViewRoot().getViewId());
    }
}

Answer 1

Open the by you given showcase link once again. Now click the Documentation tab. You'll see among others:

11.3 Exception Handler

PrimeFaces provides a built-in exception handler to take care of exceptions in ajax and non-ajax requests easily.

Configuration

ExceptionHandler and an ElResolver configured is required in faces configuration file.

<application>
     <el-resolver>
         org.primefaces.application.exceptionhandler.PrimeExceptionHandlerELResolver
    </el-resolver>
</application>
<factory>
    <exception-handler-factory>
       org.primefaces.application.exceptionhandler.PrimeExceptionHandlerFactory
    </exception-handler-factory>
</factory>

Act accordingly.