java web实现自动登录功能
本文实例为大家分享了javaweb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。
packageahpudong.com;
importjava.io.IOException;
importjava.io.PrintWriter;
importjavax.servlet.ServletException;
importjavax.servlet.annotation.WebServlet;
importjavax.servlet.http.Cookie;
importjavax.servlet.http.HttpServlet;
importjavax.servlet.http.HttpServletRequest;
importjavax.servlet.http.HttpServletResponse;
@WebServlet("/index.do")
publicclassindexextendsHttpServlet{
publicindex(){
super();
}
publicvoiddoPost(HttpServletRequestrequest,HttpServletResponseresponse)
throwsServletException,IOException{
Cookie[]cookies=request.getCookies();
if(cookies!=null){
for(Cookiecookie:cookies){
Stringname=cookie.getName();
Stringvalue=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。
packageahpudong.com;
importjava.io.IOException;
importjava.io.PrintWriter;
importjavax.servlet.ServletException;
importjavax.servlet.annotation.WebServlet;
importjavax.servlet.http.Cookie;
importjavax.servlet.http.HttpServlet;
importjavax.servlet.http.HttpServletRequest;
importjavax.servlet.http.HttpServletResponse;
@WebServlet("/login.do")
publicclassloginextendsHttpServlet{
publiclogin(){
super();
}
publicvoiddoPost(HttpServletRequestrequest,HttpServletResponseresponse)
throwsServletException,IOException{
response.setContentType("text/html");
request.setCharacterEncoding("utf-8");
response.setCharacterEncoding("utf-8");
PrintWriterout=response.getWriter();
Stringname=request.getParameter("name");
Stringpwd=request.getParameter("pwd");
Stringlogin=request.getParameter("auto");
if("chendong".equals(name)&&"123456".equals(pwd)){
if("on".equals(login)){
Cookiecookie=newCookie("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
packageahpudong.com;
importjava.io.IOException;
importjava.io.PrintWriter;
importjavax.servlet.ServletException;
importjavax.servlet.annotation.WebServlet;
importjavax.servlet.http.HttpServlet;
importjavax.servlet.http.HttpServletRequest;
importjavax.servlet.http.HttpServletResponse;
@WebServlet("/user.view")
publicclassUserextendsHttpServlet{
publicUser(){
super();
}
publicvoiddoGet(HttpServletRequestrequest,HttpServletResponseresponse)
throwsServletException,IOException{
processRequest(request,response);
}
publicvoiddoPost(HttpServletRequestrequest,HttpServletResponseresponse)
throwsServletException,IOException{
processRequest(request,response);
}
publicvoidprocessRequest(HttpServletRequestrequest,HttpServletResponseresponse)
throwsServletException,IOException{
response.setCharacterEncoding("utf-8");
PrintWriterout=response.getWriter();
Stringname=(String)request.getAttribute("name");
out.println("");
out.println("");
out.println("AServlet ");
out.println("");
out.println(""+"welcome"+name+"login"+"
");
out.println("");
out.println("");
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毛票票。