package com.shanrengo;import java.io.IOException;import javax.servlet.ServletContext;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;/*** 用戶訪問countServlet，訪問次數+1* 1.在countServlet初始化的時候，向ServletContext中保存一個訪問次數0* @author Administrator**/
public class CountServlet extends HttpServlet {@Overridepublic void init() throws ServletException {// TODO Auto-generated method stub//向ServletContext保存訪問次數0//ServletContext 中setAttribute方法//1.獲得servletContext對象ServletContext context = getServletContext();//2.保存數據context.setAttribute("visitTimes", 0);}public void doGet(HttpServletRequest request, HttpServletResponse response)throws ServletException, IOException {//每次訪問都會執行doGet//1.從servletContext中獲得visitTimesServletContext context = getServletContext();int times = (Integer) context.getAttribute("visitTimes");//2.將visitTimes++times++;//3.更新context.setAttribute("visitTimes", times);System.out.println("網站被訪問了一次！");}public void doPost(HttpServletRequest request, HttpServletResponse response)throws ServletException, IOException {doGet(request, response);}}

package com.shanrengo;import java.io.IOException;
import java.io.PrintWriter;import javax.servlet.ServletContext;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;public class CountShowServlet extends HttpServlet {public void doGet(HttpServletRequest request, HttpServletResponse response)throws ServletException, IOException {ServletContext context = getServletContext();int times = (Integer) context.getAttribute("visitTimes");response.getWriter().println(times);}public void doPost(HttpServletRequest request, HttpServletResponse response)throws ServletException, IOException {doGet(request, response);}}