Java Web Session 登录实例
package cn.com.login;import java.io.IOException;import java.io.PrintWriter;import java.util.ArrayList;import java.util.List;import javax.servlet.ServletException;import javax.servlet.http.HttpServlet;import javax.servlet.http.HttpServletRequest;import javax.servlet.http.HttpServletResponse;public class Login extends HttpServlet {private static final long serialVersionUID = 1L; protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {response.setCharacterEncoding("UTF-8");response.setContentType("text/html;charset=UTF-8");String userName=request.getParameter("userName");String password=request.getParameter("password");PrintWriter out=response.getWriter();List<User> list=Db.getAll();for(User user:list){if(user.getUserName().equals(userName)&&user.getPassword().equals(password)){request.getSession().setAttribute("user", user);response.sendRedirect("/Session/index.jsp");return ;}}out.write("用户名或者密码错误！");}protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {doGet(request,response);}}class Db{public static List<User> list=new ArrayList();static{list.add(new User("aaa","123"));list.add(new User("bbb","123"));list.add(new User("ccc","123"));}public static List<User> getAll(){return list;}}package cn.com.login;public class User {private String userName;private String password;public User() {super();// TODO Auto-generated constructor stub}public User(String userName, String password) {super();this.userName = userName;this.password = password;}public String getUserName() {return userName;}public void setUserName(String userName) {this.userName = userName;}public String getPassword() {return password;}public void setPassword(String password) {this.password = password;}}package cn.com.login;import java.io.IOException;import javax.servlet.ServletException;import javax.servlet.http.HttpServlet;import javax.servlet.http.HttpServletRequest;import javax.servlet.http.HttpServletResponse;import javax.servlet.http.HttpSession;/** * Servlet implementation class LogOut */public class LogOut extends HttpServlet {private static final long serialVersionUID = 1L;protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {HttpSession session=request.getSession(false);if(session==null){response.sendRedirect("/Session/index.jsp");return ;}session.removeAttribute("user");response.sendRedirect("/Session/index.jsp");}protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {doGet(request,response);}}<!DOCTYPE html><html> <head> <title>Index.html</title> <meta http-equiv="keywords" content="keyword1,keyword2,keyword3"> <meta http-equiv="description" content="this is my page"> <meta http-equiv="content-type" content="text/html; charset=UTF-8"> <!--<link rel="stylesheet" type="text/css" href="./styles.css">--> </head> <body> <form action="/Session/Login"> 用户名：<input type="text" name="userName"/><br/> 密码：<input type="password" name="password"/><br/> <input type="submit" value="登录" name="login"/> </form> </body></html>