2011级-csdn-java-张侃— 过滤器（自动登录）
欲实现以下操作：
利用过滤器编写登录程序，设置cookie保存时间，在有效期内重复登录可直接利用登录以后的网址登录。
创建数据库test 在此库下创建表user1
代码如下：
package com.hbsi.dao
UserDao.java
package com.hbsi.dao;
import java.util.List;
import org.apache.commons.dbutils.QueryRunner;
import org.apache.commons.dbutils.handlers.BeanHandler;
import org.apache.commons.dbutils.handlers.BeanListHandler;
import com.hbsi.domain.User;
import com.hbsi.utils.DBManager;
public class UserDao {
public List<User> getAll(){
try{
QueryRunner runner = new QueryRunner(DBManager.getDataSource());
String sql = "select * from user1";
return (List<User>) runner.query(sql,new BeanListHandler(User.class));
}catch(Exception e){
throw new RuntimeException();
}
}
public User find(String username,String password){
try{
QueryRunner runner = new QueryRunner(DBManager.getDataSource());
String sql = "select * from user1 where username=? and password=?";
Object[] params = {username,password};
return (User) runner.query(sql, params, new BeanHandler(User.class));
}catch(Exception e){
throw new RuntimeException();
}
}
public User find(String username){
try{
QueryRunner runner = new QueryRunner(DBManager.getDataSource());
String sql = "select * from user1 where username=?";
return (User) runner.query(sql, username, new BeanHandler(User.class));
}catch(Exception e){
throw new RuntimeException();
}
}
}
package com.hbsi.domain
User.java
package com.hbsi.domain;
public class User {
private String username;
private String 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 com.hbsi.filter
ZiDong.java
package com.hbsi.filter;
import java.io.IOException;
import javax.servlet.Filter;
import javax.servlet.FilterChain;
import javax.servlet.FilterConfig;
import javax.servlet.ServletException;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;
import javax.servlet.http.Cookie;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import com.hbsi.dao.UserDao;
import com.hbsi.domain.User;
public class ZiDong implements Filter {
public void destroy() {
// TODO Auto-generated method stub
}
public void doFilter(ServletRequest request, ServletResponse response,
FilterChain chain) throws IOException, ServletException {
HttpServletRequest req = (HttpServletRequest) request;
HttpServletResponse resp = (HttpServletResponse) response;
User user = (User) req.getSession().getAttribute("user");
if(user!=null){
chain.doFilter(req,resp);
return;
}
String username = null;
String password = null;
Cookie[] cookies = req.getCookies();
for(int i=0;cookies!=null && i<cookies.length;i++){
if(cookies[i].getName().equals("username")){
username = cookies[i].getValue();
}
if(cookies[i].getName().equals("password")){
password = cookies[i].getValue();
}
}
if(username==null && password==null){
chain.doFilter(req, resp);
return;
}
UserDao dao = new UserDao();
User user1 = dao.find(username);
String save_password = user1.getPassword();
if(!password.equals(save_password)){
chain.doFilter(req, resp);
return;
}
req.getSession().setAttribute("user",user1);
chain.doFilter(req, resp);
}
public void init(FilterConfig filterConfig) throws ServletException {
// TODO Auto-generated method stub
}
}
package com.hbsi.servlet
Login.java
package com.hbsi.servlet;
import java.io.IOException;
import java.io.PrintWriter;
import javax.servlet.ServletException;
import javax.servlet.http.Cookie;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import com.hbsi.dao.UserDao;
import com.hbsi.domain.User;
public class Login extends HttpServlet {
public void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
String username=request.getParameter("username");
String password=request.getParameter("password");
int autoLoginTime=Integer.parseInt(request.getParameter("autoLoginTime"));
UserDao dao=new UserDao();
User user=dao.find(username, password);
if(user!=null){
request.getSession().setAttribute("user",user);
Cookie cookie1=new Cookie("username",user.getUsername());
Cookie cookie2=new Cookie("password",user.getPassword());
cookie1.setMaxAge(autoLoginTime);
cookie2.setMaxAge(autoLoginTime);
cookie1.setPath("/DengLu");
cookie2.setPath("/DengLu");
response.addCookie(cookie1);
response.addCookie(cookie2);
response.sendRedirect("/DengLu/welcome.jsp");
}else{
request.setAttribute("message","用户名密码错误");
request.getRequestDispatcher("/cuowu.jsp").forward(request, response);
}
}
public void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
doGet(request, response);
}
}
package com.hbsi.utils
DBManager.java
package com.hbsi.utils;
import java.sql.SQLException;
import javax.sql.DataSource;
import com.mchange.v2.c3p0.ComboPooledDataSource;
public class DBManager {
private static ComboPooledDataSource ds = null;
static{
ds = new ComboPooledDataSource("mysql");
}
public static DataSource getDataSource(){
return ds;
}
}
c3p0-config.xml
<?xml version="1.0" encoding="UTF-8"?> <c3p0-config> <default-config> <property name="driverClass">com.mysql.jdbc.Driver</property> <property name="jdbcUrl">jdbc:mysql://localhost:3306/test</property> <property name="user">root</property> <property name="password">root</property> <property name="acquireIncrement">5</property> <property name="initialPoolSize">10</property> <property name="minPoolSize">5</property> <property name="maxPoolSize">20</property> </default-config> <named-config name="mysql"> <property name="driverClass">com.mysql.jdbc.Driver</property> <property name="jdbcUrl">jdbc:mysql://localhost:3306/test</property> <property name="user">root</property> <property name="password">root</property> <property name="acquireIncrement">5</property> <property name="initialPoolSize">10</property> <property name="minPoolSize">5</property> <property name="maxPoolSize">20</property> </named-config> </c3p0-config>
<?xml version="1.0" encoding="UTF-8"?>
<web-app version="2.5"
xmlns="http://java.sun.com/xml/ns/javaee"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://java.sun.com/xml/ns/javaee
http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd">
<filter>
<filter-name>ZiDong</filter-name>
<filter-class>com.hbsi.filter.ZiDong</filter-class>
</filter>
<filter-mapping>
<filter-name>ZiDong</filter-name>
<url-pattern>/*</url-pattern>
</filter-mapping>
<servlet>
<servlet-name>Login</servlet-name>
<servlet-class>com.hbsi.servlet.Login</servlet-class>
</servlet>
<servlet-mapping>
<servlet-name>Login</servlet-name>
<url-pattern>/servlet/Login</url-pattern>
</servlet-mapping>
<welcome-file-list>
<welcome-file>index.jsp</welcome-file>
</welcome-file-list>
</web-app>
JSP界面
zhu.jsp
<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
<%
String path = request.getContextPath();
String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";
%>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>
<base href="<%=basePath%>">
<title>My JSP 'zhu.jsp' starting page</title>
<meta http-equiv="pragma" content="no-cache">
<meta http-equiv="cache-control" content="no-cache">
<meta http-equiv="expires" content="0">
<meta http-equiv="keywords" content="keyword1,keyword2,keyword3">
<meta http-equiv="description" content="This is my page">
<!--
<link rel="stylesheet" type="text/css" href="styles.css">
-->
</head>
<body>
<form action="${pageContext.request.contextPath}/servlet/Login" method="post">
用户名：<input type="text" name="username"><br/>
密码：<input type="password" name="password"><br/>
有效期：<input type="radio" name="autoLoginTime" value="${60*60}">1小时
<input type="radio" name="autoLoginTime" value="${10*60}">10分钟
<input type="radio" name="autoLoginTime" value="120">2分钟<br/>
<input type="submit" value="登陆">
</form>
</body>
</html>
welcome.jsp
<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
<%
String path = request.getContextPath();
String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";
%>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>
<base href="<%=basePath%>">
<title>My JSP 'welcome.jsp' starting page</title>
<meta http-equiv="pragma" content="no-cache">
<meta http-equiv="cache-control" content="no-cache">
<meta http-equiv="expires" content="0">
<meta http-equiv="keywords" content="keyword1,keyword2,keyword3">
<meta http-equiv="description" content="This is my page">
<!--
<link rel="stylesheet" type="text/css" href="styles.css">
-->
</head>
<body>
欢迎用户${user.username}登陆
</body>
</html>
cuowu.jsp
<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
<%
String path = request.getContextPath();
String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";
%>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>
<base href="<%=basePath%>">
<title>My JSP 'cuowu.jsp' starting page</title>
<meta http-equiv="pragma" content="no-cache">
<meta http-equiv="cache-control" content="no-cache">
<meta http-equiv="expires" content="0">
<meta http-equiv="keywords" content="keyword1,keyword2,keyword3">
<meta http-equiv="description" content="This is my page">
<!--
<link rel="stylesheet" type="text/css" href="styles.css">
-->
</head>
<body>
登陆错误，请检查用户名密码是否正确！
</body>
</html>
执行结果：
登陆成功提示界面：
关闭浏览器，然后再次打开浏览器输入网址：
http://localhost:8080/DengLu/welcome.jsp
