OnPageLoad method for some pages

Question

I'm looking for a way to call a method on or before a page loads, so that I can redirect the user. The idea is to only let the user view a couple pages if they havent paid for the service yet, but have signed up. I've already implemented Form/Container based authentication and dont want to have to us anything as "big" and bulky as JAAS. Can I do this
Current I have a "hacked" solution that looks something like this:
/mysite/somepage.xhtml contains
#{someBean.hasPaid}
<bunch of code>
</bunch of code>
which then calls the someBean.myPaid before the page loads, but this feels clunky.
Is there anything else I can use? Maybe PhaseListeners? I dont quite understand how i would go about using those though?

Answer 1

Use a Filter or a PhaseListener.
If you need access to the FacesContext and some JSF managed beans, a PhaseListener is more suitable than a Filter. If you want to act on specific URL's only, a Filter may be more suitable. To create a Filter, implement javax.servlet.Filter and define it in web.xml. To create a PhaseListener, implement javax.faces.event.PhaseListener and define it in faces-config.xml.