Sorry, I don’t understand what you want to say with:
So this page can only be accessed if the action comes from a p:commandButton or p:commandLink
Clicking command buttons will result in regular HTTP requests. The only difference between regular postbacks and an user entering the URL into browser bar is the request method (POST vs GET). You COULD build a Rewrite rule to detect GET requests. But they will also be triggered, if you click on some h:link that points to the page.
Again, I’m not sure what exactly you are trying to solve. Perhaps some code examples would help to clarify your usecase.
Do you play Magic?
Get TopDecked MTG, the #1 Magic App, built by players, for players. Free to use, forever.