Servlet Session Tracker Example

This is a simple session tracker example of servlet.
import java.io.*;

import javax.servlet.*;

import javax.servlet.http.*;



public class SessionTracker extends HttpServlet {

    public void doGet(HttpServletRequest req, HttpServletResponse res) throws ServletException, IOException {

        res.setContentType("text/html");

        PrintWriter pw = res.getWriter();

        HttpSession session = req.getSession(true);

        Integer cnt = (Integer)session.getValue("tracker.cnt");

        if (cnt == null)

            cnt = new Integer(1);

        else

            cnt = new Integer(cnt.intValue() + 1);

        session.putValue("tracker.cnt", cnt);

        pw.println("<HTML><HEAD><TITLE>SessionTracker</TITLE> </HEAD>");

        pw.println("<BODY><H1>Session Tracking Demo</H1>");

        pw.println("You've visited this page " + cnt + ((cnt.intValue() == 1) ? " time." : " times."));

        pw.println("<P>");

        pw.println("<H2>Here is your session data:</H2>");

        String[] names = session.getValueNames();

        for (int i = 0; i < names.length; i++) {

            pw.println(names[i] + ": " +    session.getValue(names[i]) + "<BR>");

        }

        pw.println("</BODY></HTML>");

    }

}