java,jsp,ajax进度条（jsp）

package com.king; import java.io.IOException; import java.io.PrintWriter; import javax.servlet.ServletException; import javax.servlet.http.HttpServlet; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; /** * Servlet implementation class ProcessServlet */ public class ProcessServlet extends HttpServlet { private static final long serialVersionUID = 1L; /** * @see HttpServlet#HttpServlet() */ public ProcessServlet() { super(); // TODO Auto-generated constructor stub } /** * @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response) */ private static final String CONTENT_TYPE = "text/html; charset=GBK"; // 计数器 private int counter = 1; /** * @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response) */ protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { // 得到任务类型 String task = request.getParameter("task"); // 返回的xml字符串 String res = ""; // 第一次，创建进度条 if (task.equals("create")) { res = "<key>1</key>"; counter = 1; } else { // 完成百分比 String percent = ""; switch (counter) { case 1: percent = "10"; break; case 2: percent = "23"; break; case 3: percent = "35"; break; case 4: percent = "51"; break; case 5: percent = "64"; break; case 6: percent = "73"; break; case 7: percent = "89"; break; case 8: percent = "100"; break; } counter++; res = "<percent>" + percent + "</percent>"; } 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(); } /** * @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response) */ protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { // TODO Auto-generated method stub super.doPost(request, response); } }