Java urlconnection gets final redirected URL

Question

I have a url that redirects to another url. I want to get the final redirected URL. My code is:

public class testURLConnection { public static void main(String[] args) throws MalformedURLException, IOException { HttpURLConnection con =(HttpURLConnection) new URL( "http://tinyurl.com/KindleWireless" ).openConnection(); System.out.println( "orignal url: " + con.getURL() ); con.connect(); System.out.println( "connected url: " + con.getURL() ); InputStream is = con.getInputStream(); System.out.println( "redirected url: " + con.getURL() ); is.close(); 

}}

It always gives the original url, while redirectURL: http://www.amazon.com/Kindle-Wireless-Reading-Display-Globally/dp/B003FSUDM4/ref=amb_link_353259562_2? pf_rd_m = ATVPDKIKX0DER & pf_rd_s = center-10 & pf_rd_r = 11EYKTN682A79T370AM3 & pf_rd_t = 201 & pf_rd_p = 1270985982 &. = pf_rd_i B002Y27P3M

How can I get this final redirected URL.

This is what I tried with the loop until we get the redirect. Let's say you get the desired URL:

  public static String fetchRedirectURL(String url) throws IOException { HttpURLConnection con =(HttpURLConnection) new URL( url ).openConnection(); //System.out.println( "orignal url: " + con.getURL() ); con.setInstanceFollowRedirects(false); con.connect(); InputStream is = con.getInputStream(); if(con.getResponseCode()==301) return con.getHeaderField("Location"); else return null; } public static void main(String[] args) throws MalformedURLException, IOException { String url="http://tinyurl.com/KindleWireless"; String fetchedUrl=fetchRedirectURL(url); System.out.println("FetchedURL is:"+fetchedUrl); while(fetchedUrl!=null) { url=fetchedUrl; System.out.println("The url is:"+url); fetchedUrl=fetchRedirectURL(url); } System.out.println(url); } 

Answer 1

Try this, I use recursively to use for many redirect URLs.

 public static String getFinalURL(String url) throws IOException { HttpURLConnection con = (HttpURLConnection) new URL(url).openConnection(); con.setInstanceFollowRedirects(false); con.connect(); con.getInputStream(); if (con.getResponseCode() == HttpURLConnection.HTTP_MOVED_PERM || con.getResponseCode() == HttpURLConnection.HTTP_MOVED_TEMP) { String redirectUrl = con.getHeaderField("Location"); return getFinalURL(redirectUrl); } return url; } 

and using:

 public static void main(String[] args) throws MalformedURLException, IOException { String fetchedUrl = getFinalURL("<your_url_here>"); System.out.println("FetchedURL is:" + fetchedUrl); } 

Answer 2

 public static String getFinalRedirectedUrl(String url) { HttpURLConnection connection; String finalUrl = url; try { do { connection = (HttpURLConnection) new URL(finalUrl) .openConnection(); connection.setInstanceFollowRedirects(false); connection.setUseCaches(false); connection.setRequestMethod("GET"); connection.connect(); int responseCode = connection.getResponseCode(); if (responseCode >= 300 && responseCode < 400) { String redirectedUrl = connection.getHeaderField("Location"); if (null == redirectedUrl) break; finalUrl = redirectedUrl; System.out.println("redirected url: " + finalUrl); } else break; } while (connection.getResponseCode() != HttpURLConnection.HTTP_OK); connection.disconnect(); } catch (Exception e) { e.printStackTrace(); } return finalUrl; } 

Answer 3

My first idea would be to set instanceFollowRedirects to false or instead of URLConnection .

In both cases, the redirect will fail, so you will receive a response to your initial request. Get the HTTP status value and, if it is 3xx, get the new redirect value.

Of course, there might be a chain of redirects, so you might want to repeat the iteration until you reach a real (2xx status) page.

Answer 4

@ user719950 On my MAC-OSX - this solves the problem of a truncated HTTP URL:

Just add the following line to the source code: // You need to find in your browser what sends the request, which sends IE / Chrome. I still have no explanation why this simple setup calls the correct URL :)

 HttpURLConnection con =(HttpURLConnection) new URL ( "http://tinyurl.com/KindleWireless" ).openConnection(); con.setInstanceFollowRedirects(true); con.setDoOutput(true); System.out.println( "orignal url: " + con.getURL() ); **con.setRequestProperty("User-Agent", "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_8_2) AppleWebKit/536.26.17 (KHTML, like Gecko) Version/6.0.2 Safari/536.26.17");** con.connect(); System.out.println( "connected url: " + con.getURL() ); Thread.currentThread().sleep(2000l); InputStream is = con.getInputStream(); System.out.println( "redirected url: " + con.getURL() ); is.close(); 

Answer 5

This can help

 public static void main(String[] args) throws MalformedURLException, IOException { HttpURLConnection con = (HttpURLConnection) new URL( "http://tinyurl.com/KindleWireless").openConnection(proxy); System.out.println("orignal url: " + con.getURL()); con.connect(); con.setInstanceFollowRedirects(false); int responseCode = con.getResponseCode(); if ((responseCode / 100) == 3) { String newLocationHeader = con.getHeaderField("Location"); responseCode = con.getResponseCode(); System.out.println("Redirected Location " + newLocationHeader); System.out.println(responseCode); } } 

Answer 6

@JEETS The fetchRedirectURL function may not work because there are many HTTP codes for redirection. Change it to a range check and it will work.

 public static String fetchRedirectURL(String url) throws IOException { HttpURLConnection con =(HttpURLConnection) new URL( url ).openConnection(); //System.out.println( "orignal url: " + con.getURL() ); con.setInstanceFollowRedirects(false); con.connect(); InputStream is = con.getInputStream(); if(con.getResponseCode()>=300 && con.getResponseCode() <400) return con.getHeaderField("Location"); else return null; } 

Answer 7

This happens recursively if there are several redirects:

 protected String getDirectUrl(String link) { String resultUrl = link; HttpURLConnection connection = null; try { connection = (HttpURLConnection) new URL(link).openConnection(); connection.setInstanceFollowRedirects(false); connection.connect(); int responseCode = connection.getResponseCode(); if (responseCode == HttpURLConnection.HTTP_MOVED_PERM || responseCode == HttpURLConnection.HTTP_MOVED_TEMP) { String locationUrl = connection.getHeaderField("Location"); if (locationUrl != null && locationUrl.trim().length() > 0) { IOUtils.close(connection); resultUrl = getDirectUrl(locationUrl); } } } catch (Exception e) { log("error getDirectUrl", e); } finally { IOUtils.close(connection); } return resultUrl; }