submitform.java

this gives details of the network programming

// Sample Java code - uses URLConnection object to make an HTTP form submission
//
// Looks for a url on the command line, followed by a name and a value
// (and possibly more names and values)
// creates a query string
// from the name/value pairs and submits this content to the URL as POST data.  
//
// Example command line:
//   java SubmitForm http://monte.cs.rpi.edu/~hollingd/post/simple.cgi x 10 y 20
//   the post data will look like "x=10&y=20"

import java.net.*;
import java.io.*;

public class SubmitForm {

    public static void main(String[] args)
    throws IOException, MalformedURLException{
	if (args.length<3) {
	    System.out.println("You need to specify a URL, and a sequence of name value pairs");
	    System.exit(0);
	}

	URL u = new URL(args[0]);

	// build the POST data (query string)
	// use URLEncoder to do URL encoding
	String postdata = URLEncoder.encode(args[1]) + "=" + URLEncoder.encode(args[2]);
	for (int i=3;i+1<args.length;i+=2) {
	    postdata = postdata + "&" + URLEncoder.encode(args[i]) + "=" + URLEncoder.encode(args[i+1]);
	}
	System.out.println("Encoded query is : " + postdata );


	// Create a URLConnection object
	URLConnection uc = u.openConnection();
	
	// set it so we can write to the server (POST)
	uc.setDoOutput(true);
	
	// get something we can write to that will send ASCII
	OutputStreamWriter out =
	    new OutputStreamWriter(uc.getOutputStream(),"ASCII");

	// send the POST data, the connection handles all the other stuff

	out.write(postdata);
	out.close();


	// now lets get the response and print it out

	BufferedReader r = new BufferedReader(new InputStreamReader ( uc.getInputStream()));
	String s;
	while (	(s = r.readLine()) != null) {
	    System.out.println(s);
	}

    }
}