3

I'm a bit new to Java and more to connections stuff with it. I'm trying to create a program to connect to a website ("www.buybackprofesional.com") where I would like to download pictures and get some text from cars (after the login you have to enter a plate number to access a car's file).

This is what I have right now, but it always says that the session has expired, I need a way to login using the username and password of the mainpage, am I right? can someone give me some advice? Thanks

Note: I want to do it in Java, maybe I was not clear in the question.

        //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);
        }

A colleage helped me with this so I'll post the 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;
}

This will submit the form info on the page I need and after that, using cookies I can stay connected!

oli206
  • 413
  • 6
  • 16
  • You can find here some hints: [How to use URLConnection?](http://stackoverflow.com/questions/2793150/how-to-use-java-net-urlconnection-to-fire-and-handle-http-requests) – BalusC Aug 03 '10 at 22:21

1 Answers1

1

To connect to a website using java consider using httpunit or httpcore (offered by apache). They handle sessions much better then you (or I) could do on your own.

Edit: Fixed the location of the link. Thanks for the correction!

John Vint
  • 37,722
  • 6
  • 69
  • 104
  • 1
    http://svn.apache.org/repos/asf/httpcomponents/httpclient/tags/4.0.1/httpclient/src/examples/org/apache/http/examples/client/ClientAuthentication.java – rancidfishbreath Aug 03 '10 at 22:19
  • 1
    The above link shows how to use Apache httpcomponents client which is the higher level user API built on top of httpcore. You really should be using the higher level API if you are new to Java. http://hc.apache.org/ – rancidfishbreath Aug 03 '10 at 22:22
  • Thanks!, I'll try your suggestions – oli206 Aug 04 '10 at 06:20