/* * DynamicUpdateServlet.java * * Created on June 26, 2005, 2:39 PM */package ajaxbook.chap4;import java.io.*;import java.net.*;import javax.servlet.*;import javax.servlet.http.*;/** * * @author nate * @version */public class DynamicUpdateServlet extends HttpServlet {    private int counter = 1;        /** Handles the HTTP <code>GET</code> method.     * @param request servlet request     * @param response servlet response     */    protected void doGet(HttpServletRequest request, HttpServletResponse response)    throws ServletException, IOException {        String res = "";        String task = request.getParameter("task");        String message = "";                        if (task.equals("reset")) {            counter = 1;        } else {            switch (counter) {                case 1: message = "Steve walks on stage"; break;                case 2: message = "iPods rock"; break;                case 3: message = "Steve says Macs rule"; break;                case 4: message = "Change is coming"; break;                case 5: message = "Yes, OS X runs on Intel - has for years"; break;                case 6: message = "Macs will soon have Intel chips"; break;                case 7: message = "done"; break;            }            counter++;        }        res = "<message>" + message + "</message>";                PrintWriter out = response.getWriter();        response.setContentType("text/xml");        response.setHeader("Cache-Control", "no-cache");        out.println("<response>");        out.println(res);        out.println("</response>");        out.close();    }        /** Handles the HTTP <code>POST</code> method.     * @param request servlet request     * @param response servlet response     */    protected void doPost(HttpServletRequest request, HttpServletResponse response)    throws ServletException, IOException {        doGet(request, response);    }        /** Returns a short description of the servlet.     */    public String getServletInfo() {        return "Short description";    }}