how to (simply) generate POST http request from java to do the file upload

public void post(String url) throws Exception {
	URL u = new URL(url);
	URLConnection c = u.openConnection();

	c.setDoOutput(true);
	if (c instanceof HttpURLConnection) {
		((HttpURLConnection)c).setRequestMethod("POST");
	}

	OutputStreamWriter out = new OutputStreamWriter(
		c.getOutputStream());

	// output your data here

	out.close();

	BufferedReader in = new BufferedReader(
			    new InputStreamReader(
		     		c.getInputStream()));

	String s = null;
	while ((s = in.readLine()) != null) {
		System.out.println(s);
	}
	in.close();
}