Why i can't get parameters from the url sent by Facebook after '#' character

Question

I'm trying to make login to facebook according to Facebook Server-Side Authentication flow using jsp and servlets. I was succsessfuly login to my fb account but when fb is redirecting to my app, it sends the parameters (state...) after the character '#'. I was looking at this: http://facebook.stackoverflow.com/questions/4144878/get-url-parameters-after-in-java .

but i'm doing it in a different way then they do.

here's my code:

response.sendRedirect(response.encodeRedirectURL("http://www.facebook.com/dialog/oauth/?client_id=343473222406382" +
                "&redirect_uri=http://localhost:8080/accountsLogger&response_type=token&state=logged"));

and i'm redirecting to:

{http://localhost:8080/accountsLogger/#state=logged&access_token=AAAE4YxdpUO4BAILjJoj5GsFZBDir1YmZCy4ZC9BmZAOCAztC2QclKo46OSce7dzObL6lSzrYpRDgQycOzzhfbqThR6kVC16lmurC5X5oV1lIrsvI0h9D&expires_in=4329.}

Answer 1

The FB API is built (largely) to be used client-side. The hash-portion of the URL (what is after the '#') is never sent to the server by the browser (which is why you can't pick it up). If you need this information server-side, you need to pick it up using javascript on your accountsLogger page ( document.location.hash ), convert the "hash parameters" into "regular" url-parameters on another URL and redirect the page to that URL.

Answer 2

URL after # is not sent to the server. It's originally intended as an anchor, it is, something to refer on the downloaded page. The browser then do:

GET /your/url.htm?param1=value&param2=value

and if there's #someanchor at the end the browser tries to position the page to make that anchor visible (if it exists).

Old school anchor:

<a name="someanchor">Hello</a>

Standard HTML anchor:

<p id="someanchor">Hello</p> (thanks @Jon Hanna)