本文实例为大家分享了java实现自动登录的具体代码,供大家参考,具体内容如下
- 当你勾选(记住登录状态),用cookie保存用户名和密码。不勾选,cookie失效。
- 所有的页面都要经过autoLoginFilter.java 的过滤器,在这类中,必须要判断cookies不为null,获得所有的cookie,得到name为user的cookie,进行用户名和密码的验证,如果不为null,则将user存入session。
- 在LoginServlet.java中,获得username和password参数,进行dao验证,如果不为空,放入seesion中,进行页面跳转。
- 创建cookie对象。setpath("/"),表示本应用下的所有路径都能访问此cookie。
- 对于已经正确登录的用户,再次访问其他页面必定会再次经过autoLoginFilter,这时,判断当前session中的user是否为null,不为null,直接通过。
- 对于**login.jsp的有关页面,不需要经过autoLoginFilter。
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
|
package com.learning.web.servlet;
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 com.learning.domain.User;
import com.learning.service.UserService;
@WebServlet ( "/servlet/loginServlet" )
public class LoginServlet extends HttpServlet {
private static final long serialVersionUID = 1L;
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
String username = request.getParameter( "username" );
String password = request.getParameter( "password" );
String autologin = request.getParameter( "autologin" );
UserService userService= new UserService();
User user = userService.findUser(username, password);
//user不为null,则登录成功
if (user!= null ) {
//创建cookie来保存用户信息
Cookie cookie= new Cookie( "user" , user.getUsername()+ "&" +user.getPassword());
cookie.setPath( "/" );
//autologin不为null,则记住了登录状态
if (autologin!= null ) {
cookie.setMaxAge( 1 * 60 * 60 * 24 ); //一天的有效时间
}
else {
cookie.setMaxAge( 0 );
}
response.addCookie(cookie);
request.getSession().setAttribute( "user" , user);
request.getRequestDispatcher( "/home.jsp" ).forward(request, response);
} else {
response.sendRedirect(request.getContextPath()+ "/homeLogin.jsp" );
}
}
protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
doGet(request, response);
}
}
|
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
|
package com.learning.web.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.annotation.WebFilter;
import javax.servlet.annotation.WebInitParam;
import javax.servlet.http.Cookie;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;
import javax.servlet.jsp.jstl.core.Config;
import com.learning.domain.User;
import com.learning.service.UserService;
@WebFilter (urlPatterns= "/*" ,initParams={ @WebInitParam (name= "autologin" ,value= "login" ), @WebInitParam (name= "" ,value= "" )})
public class AutoFilter implements Filter{
private FilterConfig filterConfig;
@Override
public void destroy() {
}
@Override
public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain)
throws IOException, ServletException {
// 转换对象
HttpServletRequest httpServletRequest = (HttpServletRequest) request;
HttpServletResponse httpServletResponse = (HttpServletResponse) response;
// 获得访问的路径
String uri = httpServletRequest.getRequestURI();
String contextPath = httpServletRequest.getContextPath();
uri = uri.substring(contextPath.length() + 1 );
// 获得初始化参数
String login = filterConfig.getInitParameter( "autologin" );
System.out.println( "直接通行的路径:" +login);
// 不包含"login"的路径就要进行过滤 (xxxlogin.jsp 不需要自动登录)
if (!uri.contains(login)) {
HttpSession session = httpServletRequest.getSession();
User u = (User) session.getAttribute( "user" );
if (u != null ) {
System.out.println( "session不为null" );
chain.doFilter(request, response);
} else {
// 处理业务逻辑
// 1.获得cookie 得到User的信息
String username = "" ;
String password = "" ;
UserService userService = new UserService();
Cookie[] cookies = httpServletRequest.getCookies();
for ( int i = 0 ;cookies!= null && i < cookies.length; i++) {
if ( "user" .equals(cookies[i].getName())) {
String string = cookies[i].getValue();
String[] values = string.split( "&" );
username = values[ 0 ];
password = values[ 1 ];
User user = userService.findUser(username, password);
// 不为空则放入session
if (user != null ) {
System.out.println( "自动登录了" );
httpServletRequest.getSession().setAttribute( "user" , user);
}
}
}
}
}
// 2.放行
chain.doFilter(request, response);
}
@Override
public void init(FilterConfig filterConfig) throws ServletException {
this .filterConfig=filterConfig;
}
}
|
以上就是本文的全部内容,希望对大家的学习有所帮助,也希望大家多多支持服务器之家。