java.net.ProtocolException: Server redirected too many times（20）

If the above doesn't apply, you may try to use the following code (hack) to skip the re-direction,
            get the Location header and re-connect:
           
            try {
                  URL url = new URL("http://www.ama.org/events ");
                  HttpURLConnection con = (HttpURLConnection) url.openConnection();
                  con.setFollowRedirects(true);
                  con.setInstanceFollowRedirects(false);
                  con.connect();
             
              while (String.valueOf(con.getResponseCode()).startsWith("3")) {
                 String theLocation = con.getHeaderField("Location");
                 con.disconnect();
                 url = new URL(theLocation);
                 con = (HttpURLConnection) url.openConnection();
                 con.setFollowRedirects(true);
                 con.setInstanceFollowRedirects(false);
                 con.connect();
                 }
                 /** at this point you are located at the last(target)page of
                     redirection chain */
             
            } catch (Exception ex) { ex.printStackTrace(); }