创建一个index.jsp页面
<%@ page language="java" contentType="text/html; charset=utf-8" pageEncoding="utf-8"%> <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> <html> <head> <meta http-equiv="Content-Type" content="text/html; charset=utf-8"> <title>Insert title here</title> </head> <body> <form action="login" method="post"> 用户名:<input type="text" name="uid" /><br> 密码:<input type="password" name="pwd" /><br> <input type="submit" value="登录"> </form> </body> </html>
创建一个main.jsp页面
<%@ page language="java" contentType="text/html; charset=ISO-8859-1" pageEncoding="ISO-8859-1"%> <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> <html> <head> <meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1"> <title>Insert title here</title> </head> <body> <%-- if(session.getAttribute("user")==null){ response.sendRedirect("index.jsp"); } --%> <% Cookie[] cc = request.getCookies(); boolean has = false; for(Cookie c:cc){ if(c.getName().equals("user")){ has=true; } } if(has==false){ response.sendRedirect("index.jsp"); } %> welcome:<%=session.getAttribute("user") %> <% for(Cookie c:cc){ if(c.getName().equals("user")){ out.print(c.getValue()); } } %> </body> </html>
创建一个servlet界面，名为Login
package com.ceshi; import java.io.IOException; import javax.servlet.ServletException; import javax.servlet.annotation.WebServlet; import javax.servlet.http.Cookie; import javax.servlet.http.HttpServlet; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import javax.servlet.http.HttpSession; /** * Servlet implementation class Login */ @WebServlet("/login") public class Login extends HttpServlet { private static final long serialVersionUID = 1L; /** * @see HttpServlet#HttpServlet() */ public Login() { super(); // TODO Auto-generated constructor stub } /** * @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response) */ protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { // TODO Auto-generated method stub //response.getWriter().append("Served at: ").append(request.getContextPath()); String uid = request.getParameter("uid"); String pwd = request.getParameter("pwd"); //HttpSession session= request.getSession(); //session.setAttribute("user",uid); Cookie c = new Cookie("user", uid); response.addCookie(c); response.sendRedirect("main.jsp"); } /** * @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response) */ protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { // TODO Auto-generated method stub doGet(request, response); } }
显示如下：
