自己Cookie写的自动登录功能包含BASE64 和MD5的使用

sql表

username password字段

User类

有 id username password等字段

Service有一函数

1 @Override
2 
3 public User findUser(String username) 
4 {
5     return userDao.findUser(username);
6 }

实现

1     @Override
2     public User findUser(String username) {
3         try {
4             return qr.query("select * from user where username=?", new BeanHandler<User>(User.class),username);
5         } catch (SQLException e) {
6             throw new DaoException(e);
7         }
8     }

Utils

WEBUtils.java

 1 package cn.itcast.util;
 2 
 3 import java.lang.reflect.InvocationTargetException;
 4 import java.security.MessageDigest;
 5 import java.security.NoSuchAlgorithmException;
 6 
 7 import javax.servlet.http.Cookie;
 8 import javax.servlet.http.HttpServletRequest;
 9 import javax.servlet.http.HttpServletResponse;
10 
11 import org.apache.commons.beanutils.BeanUtils;
12 
13 import sun.misc.BASE64Encoder;
14 
15 
16 public class WebUtils {
17 
18     public static <T> T fillBean(HttpServletRequest request,
19             Class<T> clazz) {
20         try {
21             T t=clazz.newInstance();
22             BeanUtils.populate(t,request.getParameterMap());
23             return t;
24         } catch(Exception e) {
25             throw new RuntimeException(e);
26         }
27     }
28 
29     public static void addAutoLoginFunction(HttpServletRequest request,
30             HttpServletResponse response) {
31         
32         
33         String username=request.getParameter("username");
34         String password=request.getParameter("password");
35         //把帐号BASE64加密 _ 密码双次md5加密， 所以比较的时候 数据库中密码取出md5加密再和这个比较
36         
37         String encodeUsername=new BASE64Encoder().encode(username.getBytes());
38         String encodePassword=Md5Util.md5(password);
39         System.out.println("存入数据库 帐号:"+username);
40         System.out.println("存入数据库 密码:"+password);
41         System.out.println("存入Cookie 帐号:"+encodeUsername);
42         System.out.println("存入Cookie密码:"+encodePassword);
43         Cookie c=new Cookie("loginInfo",encodeUsername+"_"+encodePassword);
44         c.setMaxAge(10000);
45         c.setPath(request.getContextPath());
46         response.addCookie(c);
47     }
48     //删除Cookie
49     public static void removeAutoLoginCookie(HttpServletRequest request,
50             HttpServletResponse response) {
51         Cookie cs[]=request.getCookies();
52         if(cs!=null)
53         {
54             for(Cookie c:cs)
55             {
56                 if(c.getName().equals("loginInfo"))
57                 {
58                     Cookie cookie=new Cookie("loginInfo",null);
59                     cookie.setMaxAge(0);
60                     cookie.setPath(request.getContextPath());
61                     response.addCookie(cookie);
62 //                    c.setMaxAge(0);
63 //                    c.setPath(request.getContextPath());
64                     System.out.println("删除Cookie");
65                     return;
66                 }
67             }
68         }
69     }
70     
71 
72 
73 }

MD5Util.java

 1 package cn.itcast.util;
 2 
 3 import java.security.MessageDigest;
 4 import java.security.NoSuchAlgorithmException;
 5 
 6 import sun.misc.BASE64Encoder;
 7 
 8 public class Md5Util {
 9     public static String md5(String message){
10         try{
11             MessageDigest md = MessageDigest.getInstance("md5");
12             byte b[] = md.digest(message.getBytes());
13             return new BASE64Encoder().encode(b);
14         }catch(Exception e){
15             throw new RuntimeException(e);
16         }
17     }
18 }

Servlet中由doGet()引出以下两个方法 operation=login operation=logout

    private void logout(HttpServletRequest request, HttpServletResponse response) throws IOException {
        //移除Cookie 去除自动登录功能
        WebUtils.removeAutoLoginCookie(request,response);
        request.getSession().invalidate();
        response.sendRedirect(request.getContextPath());
    }

    private void login(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        String username=request.getParameter("username");
        String password=request.getParameter("password");
        BusinessService serviceDao=new BusinessServiceImpl();
        password=Md5Util.md5(password);
        User user=serviceDao.login(username,password);
        if(null==user)
        {
            request.setAttribute("message", "用户名或者密码错误");
            request.getRequestDispatcher("/client/message.jsp").forward(request, response);
        }
        else
        {
            request.getSession().setAttribute("user", user);
            String autoLogin=request.getParameter("autologin");
            if(null!=autoLogin)
            {
                //添加自动登录功能
                WebUtils.addAutoLoginFunction(request,response);
            }
            response.sendRedirect(request.getContextPath());
        }
    }

filter过滤器中配置

 1 package cn.itcast.web.filter;
 2 
 3 import java.io.IOException;
 4 
 5 import javax.servlet.Filter;
 6 import javax.servlet.FilterChain;
 7 import javax.servlet.FilterConfig;
 8 import javax.servlet.ServletException;
 9 import javax.servlet.ServletRequest;
10 import javax.servlet.ServletResponse;
11 import javax.servlet.http.Cookie;
12 import javax.servlet.http.HttpServletRequest;
13 import javax.servlet.http.HttpServletResponse;
14 import javax.servlet.http.HttpSession;
15 
16 import sun.misc.BASE64Decoder;
17 
18 import cn.itcast.domain.User;
19 import cn.itcast.service.BusinessService;
20 import cn.itcast.service.impl.BusinessServiceImpl;
21 import cn.itcast.util.Md5Util;
22 
23 public class AutoLoginFilter implements Filter {
24 
25     @Override
26     public void init(FilterConfig filterConfig) throws ServletException {
27         
28     }
29 
30     @Override
31     public void doFilter(ServletRequest req, ServletResponse resp,
32             FilterChain chain) throws IOException, ServletException {
33 
34         HttpServletRequest request = (HttpServletRequest)req;
35         HttpServletResponse response = (HttpServletResponse)resp;
36         BusinessService bService=new BusinessServiceImpl();
37         HttpSession session = request.getSession();
38         User u = (User)session.getAttribute("user");
39         if(null==u)////只有没有登录时才自动登录，已经登录了就不需要了
40         {
41             System.out.println("自动登录开始执行");
42             //1、获取名称为loginInfo的cookie
43             Cookie loginInfoCookie=null;
44             Cookie cs[]=request.getCookies();
45             if(null!=cs)
46             {
47                 for(Cookie c:cs)
48                 {
49                     if("loginInfo".equals(c.getName()))
50                     {
51                         loginInfoCookie=c;
52                         break;
53                     }
54                 }
55             }
56             //2、有：取出cookie的值：用户名_加密的密码
57             if(null!=loginInfoCookie)
58             {
59                 String usernamePassword=loginInfoCookie.getValue();
60                 System.out.println("帐号密码整串:"+usernamePassword);
61                 //3、拆出用户名和密码
62                 String username=usernamePassword.split("\\_")[0];
63                 String password=usernamePassword.split("\\_")[1];
64                 //根据登录的时候 username password放入Cookie的原理
65                 //username BASE64解密
66                 username=new String(new BASE64Decoder().decodeBuffer(username));
67                 System.out.println("Cookie的用户:"+username);
68                 System.out.println("Cookie的密码:"+password);
69                 User user=bService.findUser(username);
70                 if(null!=user)
71                 {
72                     System.out.println("Cookie的用户:"+user.getUsername());
73                     System.out.println("Cookie的密码:"+Md5Util.md5(user.getPassword()));
74                     //4、再次验证用户名和密码是否正确（根据用户名查出密码，加密后再与cookie中的那个密码进行比对）
75                     //将数据库查出的密码 md5加密和cookie中的密码相比
76                     if(Md5Util.md5(user.getPassword()).equals(password))
77                     {
78                         //5、正确：得到用户对象，放到HttpSession中（自动登录）
79                         session.setAttribute("user", user);
80                         //自动登录搞定
81                         System.out.println("自动登录完成");
82                     }
83                 }
84             }
85         }
86         //放行
87         chain.doFilter(request, response);
88     }
89 
90     @Override
91     public void destroy() {
92         
93     }
94 
95 }

web.xml中可以配置对指定的页面进行自动登录的过滤器，因为放到session中，所以不需要每个页面都过滤

url-pattern 配置过滤地址

posted on 2014-05-29 16:17 wf110 阅读(1774) 评论(0) 编辑收藏举报

自己Cookie写的自动登录功能 包含BASE64 和MD5的使用

自己Cookie写的自动登录功能包含BASE64 和MD5的使用