我在 eclipse 中使用 JSP 编写了一个 Web 应用程序。它有登录页面和其他页面。在我部署并尝试访问其他页面后,我可以使用登录页面无需登录即可访问。因此,每当用户在通过登录页面登录之前尝试访问其他页面 url 时,我想重定向到登录页面。怎么做?如果有人在这方面帮助我,我将不胜感激。
谢谢
最佳答案
您甚至可以查找:Click here 。您必须实现一个逻辑来检查每个页面上的用户凭据(登录用户名或登录密码)详细信息。如果存在详细信息,则进一步处理,否则重定向到错误页面。现在我已经实现了一个逻辑,该逻辑在登录后设置登录属性,如果未将错误消息设置到 session 中,它将所有数据设置到 session 中。通常我们会将 UserClass 存储到 session 中,因为这是为了您的知识,这就是我在 session 中添加两个属性的原因。
LoginServlet.java
package com.servlets;
import java.io.IOException;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;
@WebServlet("/LoginServlet")
public class LoginServlet extends HttpServlet {
private static final long serialVersionUID = 1L;
public LoginServlet() {
super();
// TODO Auto-generated constructor stub
}
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
// TODO Auto-generated method stub
response.getWriter().append("Served at: ").append(request.getContextPath());
}
/**
* @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)
*/
protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
// TODO Auto-generated method stub
String uname=request.getParameter("uname");
String pword=request.getParameter("pword");
if(null!=uname && uname!="" && pword!=null && pword!=""){
HttpSession session=request.getSession(true);
session.setAttribute("uname", uname);
session.setAttribute("pword", pword);
response.getWriter().append("Login SucessFully");
}else{
response.sendRedirect("index.jsp"); //error
HttpSession session=request.getSession(true);
session.setAttribute("errorMessage", "Login Failed ");
}
//doGet(request, response);
}
}
index.jsp:
<!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=windows-1256">
<title>Login Page</title>
</head>
<%
String errorMessage = (String) session.getAttribute("errorMessage");
if (null !=errorMessage) { %>
<h4> <%=errorMessage %></h4>
<%}
%>
<body>
<form action="LoginServlet" method="post" >
Please enter your username <input type="text" name="uname" id="uname" />
<br>
Please enter your password <input type="text" name="pword" id="pword" />
<input type="submit" value="submit">
</form>
</body>
</html>
PostLogin.jsp
<%@ page language="java" contentType="text/html; charset=ISO-8859-1"
pageEncoding="ISO-8859-1"%>
<!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=ISO-8859-1">
<title>Simple Page which can't be access without Login</title>
</head>
<%
String uname = (String) session.getAttribute("uname");
if (null == uname) {
session.setAttribute("errorMessage", "Login Failed ");
response.sendRedirect("userLogged.jsp");
}
%>
<body>
<h4>Simple Page which can be access without Login </h4>
</body>
</html>
希望这对您有帮助,祝您好运。如果您还需要其他详细信息,请告诉我
关于javascript - 如果用户尚未登录,Java servlet如何重定向到jsp登录页面?,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/46966452/