I used the same sample code Primefaces has in its web page:
<h:commandLink value="Excel">
<p:dataExporter type="xls" target="dataTable" fileName="boo" pageOnly="true"/>
</h:commandLink>
But does not work. In Internet Explorer browser gives the following message:
Details of the errors of the web page Message: Unexpected call to method or property access.
Nothing ever happens in Mozilla Firefox.
What might be happening?
javax.servlet.ServletException: org/apache/poi/ss/usermodel/RichTextString
Look further down in the stacktrace. I bet that the root cause is either a NoClassDefFoundError or ClassNotFoundException? In that case, this just means that you forgot to install Apache POI.
Download this Apache POI zip file, extract it, put poi-3.8-20120326.jar in /WEB-INF/lib folder and rebuild/redeploy/restart the webapp.