JavaWeb使用Cookie模拟实现自动登录功能(不需用户名和密码)

Z时代
2024-01-10
分类：综合

其中包含两个jsp文件，分别为login.jsp和index.jsp

代码如下:


<%@ page language="java" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>登录界面</title>
</head>
<body>
<form action="index.jsp" method="post">
用户名:<input type="text" name="name"/>
<input type="submit" value="提交"/>
</form>
</body>
</html>

index.jsp


<%@ page language="java" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>欢迎您</title>
</head>
<body>
<%
String name = request.getParameter("name");
if(name != null && !name.trim().equals("")){
Cookie cookie = new Cookie("name",name);
cookie.setMaxAge(30); //设置cookie有效期为30s
response.addCookie(cookie);
}else{
Cookie[] cookies = request.getCookies();
if(cookies != null && cookies.length > 0){
for(Cookie cookie:cookies){
String cookieName = cookie.getName();
if("name".equals(cookieName)){
String val = cookie.getValue();
name = val;
}
}
}
}
if(name != null && !name.trim().equals("")){
out.print("hello: " + name);
}else{//否则重定向到登录界面
response.sendRedirect("login.jsp");
}
%>
</body>
</html>