Question

I want to use a normal spring mvc controler and request mapping using path variables.

I do not want to forward or redirect, just change the string that user sees.

@RequestMapping(value = "/Foo/{id}/*", method = RequestMethod.GET)
public ModelAndView getFoo(@PathVariable final String friendlyUrl) {
//how can I rewite the url that user sees ?
}

(the same behaviour as when you change the title of an existing question on stackoverflow)

Answer 1

If you watch the traffic in wireshark, firebug or something you see, that stackoverflow sends a HTTP 301 Moved Permanently to the final URL.
You could do the same.

For this you need the HttpServletResponse, you can add it to the method signature to get it injected.
Set the permanent redirect:

String rightUrl = urlCompleter.complete(friendlyUrl);
response.setStatus(HttpServletResponse.SC_MOVED_PERMANENTLY);
response.setHeader("Location", rightUrl);

Where you need to implement urlCompleter on your own, eg. look in the database table of entries and locate the right url component.