Return to previous page after login

I have a conceptual question.
Regretfully my struts experiences are limited to what I have learned from a couple of books, but I find myself stuck with this conceptual problem.

Say for instance I'm trying to add a new customer, before adding the customer I need to be 'logged in' (assume I was logged in originally, but the session has timed out), I know how to forward to a login page, what i don't understand is having logged in, how do I get back to my add new customer page. If you assume the login page will be called from many different pages, how to I tell it what page to go to after loggin in?

I know how to get back to a specific page, eg Welcome page

Am I thinking about this the correct way?

Your guidance and advise appreciated.

If you want to do some action and return to the current action you can use
mappimg.getInputForward().