try{
        URL siturl = new URL("https://web.expasy.org/cgi-bin/protparam/protparam");
        //opening the siturl connection
        HttpURLConnection conn = null;
        conn = (HttpURLConnection)siturl.openConnection();
        conn.setRequestMethod("POST");
        conn.setFollowRedirects(true);
        char[] data=new String("prot_id=P05130&sequence=&mandatory=").toCharArray();
        conn.setRequestProperty("Content-length", String.valueOf(data.length));
        conn.setRequestProperty("Content-Type", "application/x-www-form-urlencoded");
        conn.setDoOutput(true);
        conn.setDoInput(true);
        //setting the output condition to true for printing the contents
        OutputStreamWriter wr = new OutputStreamWriter(conn.getOutputStream());
        // used to convert character to bytes
        wr.write(data);
        //System.out.println(data);
        wr.flush();
        wr.close();
        // Get the response
        BufferedReader rd = new BufferedReader(new InputStreamReader(conn.getInputStream()));
        String line=null;
        while((line=rd.readLine())!=null){
            System.out.println(line);
        }
        }catch(Exception e){
            e.printStackTrace();
        }