本文实例为大家分享了java web实现自动登录功能的具体代码,供大家参考,具体内容如下
主要思路就是:当用户访问网站的首页时,浏览器端会先检擦浏览器中存在的cookie中是否又登录的用户的用户名,如果有,则直接跳转至用户登录好的界面,如果没有,则重定向至登录界面,在服务器端创建该用户登录的cookie,响应时,将创建的cookie返回至浏览器端保存。
一、用户访问首页时检查cookie是否存在。
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package ahpudong.com; import java.io.IOException; import java.io.PrintWriter; 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; @WebServlet ( "/index.do" ) public class index extends HttpServlet { public index() { super (); } public void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { Cookie[] cookies=request.getCookies(); if (cookies!= null ){ for (Cookie cookie:cookies){ String name=cookie.getName(); String value=cookie.getValue(); if ( "name" .equals(name) && "chendong" .equals(value)){ request.setAttribute(name, value); request.getRequestDispatcher( "user.view" ).forward(request, response); return ; } } } response.sendRedirect( "login.jsp" ); } } |
二、确定用户登录的cookie不存在,在手动登录的过程中创建用户登录cookie。
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package ahpudong.com; import java.io.IOException; import java.io.PrintWriter; 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; @WebServlet ( "/login.do" ) public class login extends HttpServlet { public login() { super (); } public void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { response.setContentType( "text/html" ); request.setCharacterEncoding( "utf-8" ); response.setCharacterEncoding( "utf-8" ); PrintWriter out = response.getWriter(); String name=request.getParameter( "name" ); String pwd=request.getParameter( "pwd" ); String login=request.getParameter( "auto" ); if ( "chendong" .equals(name) && "123456" .equals(pwd)){ if ( "on" .equals(login)){ Cookie cookie= new Cookie( "name" , "chendong" ); cookie.setMaxAge( 7 * 24 * 60 * 60 ); //有效期为一个星期 response.addCookie(cookie); request.setAttribute( "name" ,name); request.getRequestDispatcher( "user.view" ).forward(request, response); } } else { response.sendRedirect( "login.jsp" ); } } } |
三、登录成功时的视图层
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package ahpudong.com; import java.io.IOException; import java.io.PrintWriter; import javax.servlet.ServletException; import javax.servlet.annotation.WebServlet; import javax.servlet.http.HttpServlet; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; @WebServlet ( "/user.view" ) public class User extends HttpServlet { public User() { super (); } public void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { processRequest(request,response); } public void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { processRequest(request,response); } public void processRequest(HttpServletRequest request,HttpServletResponse response) throws ServletException, IOException{ response.setCharacterEncoding( "utf-8" ); PrintWriter out=response.getWriter(); String name=(String) request.getAttribute( "name" ); out.println( "<!DOCTYPE HTML PUBLIC \"-//W3C//DTD HTML 4.01 Transitional//EN\">" ); out.println( "<HTML>" ); out.println( " <HEAD><TITLE>A Servlet</TITLE></HEAD>" ); out.println( " <BODY>" ); out.println( "<h1>" + "welcome " +name+ " login" + "</h1>" ); out.println( " </BODY>" ); out.println( "</HTML>" ); out.flush(); out.close(); } } |
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。
原文链接:http://blog.csdn.net/chendongqaq/article/details/78298938