Connect to a website that requires a user password / password

Question

I am a little new to Java and more connected with it. I am trying to create a program to connect to a website ("www.buybackprofesional.com"), where I would like to upload photos and get text from cars (after logging in you must enter the plate number to access the car file).

This is what I have right now, but he always says that the session has expired, I need a way to log in using the username and password of the main page, am I right? can anyone give me some advice? Thanks

Note. I want to do this in Java, maybe I was not in this matter.

        //URL web = new URL("http://www.buybackprofesional.com/DetallePeri.asp?mat=9073FCV&fec=27/07/2010&tipo=C&modelo=4582&Foto=0");
        URL web = new URL("http://www.buybackprofesional.com/");
        HttpURLConnection con = (HttpURLConnection) web.openConnection();
        con.setRequestMethod("GET");
        con.setRequestProperty("User-Agent", "Mozilla/4.0 (compatible; JVM)");
        con.setRequestProperty("Pragma", "no-cache");
        con.connect();
              BufferedReader reader = new BufferedReader(new InputStreamReader(con.getInputStream()));
        String line = null;
        while ((line = reader.readLine()) != null) {
            System.out.println(line);
        }                  

The assistant helped me, so I will write code that works:

public static URLConnection login(String _url, String _username, String _password) throws IOException, MalformedURLException {

    String data = URLEncoder.encode("Usuario", "UTF-8") + "=" + URLEncoder.encode(_username, "UTF-8");
    data += "&" + URLEncoder.encode("Contrase", "UTF-8") + "=" + URLEncoder.encode(_password, "UTF-8");

    // Send data
    URL url = new URL(_url);
    URLConnection conn = url.openConnection();
    conn.setDoOutput(true);

    OutputStreamWriter wr = new OutputStreamWriter(conn.getOutputStream());
    wr.write(data);
    wr.flush();
    wr.close();
    return conn;
}

, , , !

Answer 1

- java, httpunit httpcore ( apache). , ( ) .

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