java jsf problem with site loading find bug

i am currently learning java jsf and i have a site loading problem. when the application is started first time everything is fine. but when i click the link (Shop-Cash), which should reload the current page and some data from database its redirecting to a blank new site. attached is a netbeans project file. this project is about finding the error and tell me what i was doing wrong. don't rewrite anything and then send different code back. i only want the info.