Can I extract information from a webpage that is generated by javascript?

Question

I am trying to keep a track of the number of a forum's online viewer such as this website
http://club.chinaren.com/The online viewer number is placed at the left top area as �������� (misdisplayed Chinese characters) [number]���� which means "Currently online: [number] people"
I checked its html source and find it was generated by javascript as
<div class="cr1bg">������<span> <script>getTotalBoardUser()</script></span>��</div></div></div></div>After I saved the webpage to my local disk, I found the getTotalBoardUser() defintion in a .js file named club_olusers.js like:
totalBoardUsers = 23565;
function getTotalBoardUser() {
     document.write(totalBoardUsers);
}Now I want to extract the totalBoardUsers value.
Is it possible? How to do that?
Thanks!
Edited by: aaron9979215 on Jun 15, 2008 2:18 AM

Answer 1

Here's a way:
import java.io.*;
import java.net.*;
import java.util.*;
public class Test {
    public static void main(String[] args) throws MalformedURLException, IOException {
        String url = "http://club.chinaren.com/club_olusers.js";
        Scanner jsFile = new Scanner(new URL(url).openStream());
        while(jsFile.hasNextLine()) {
            String line = jsFile.nextLine().trim();
            if(line.matches("totalBoardUsers\\s+=\\s+\\d+;")) {
                System.out.println(line.replaceAll("[^\\d]+", ""));
                break;
}