Java 登录Servlet需要两次尝试

前言：总java nube

我有一个带有/index.jsp的新web应用程序，它正在通过一个登录servlet，然后如果在登录servlet期间一切正常，就转发到/web-INF/index.jsp

Servlet：

import java.io.*;
import com.<co>.<app>.User;
import java.sql.SQLException;
import javax.servlet.http.Cookie;
import javax.servlet.http.HttpServlet;
import javax.servlet.ServletException;
import javax.naming.NamingException;
import javax.servlet.RequestDispatcher;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

@WebServlet(name = "Login", urlPatterns = { "/Login" })
public class Login extends HttpServlet {

    public Login() { super(); }
    private static String userid = null;
    private static String passwd = null;
    private static final long serialVersionUID = 1L;

    protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException
    {
        userid = request.getParameter("userid");
        passwd = request.getParameter("passwd");
        if (passwd.length()==0){ passwd = null; }
        else { passwd.trim(); }

        if (userid != null && passwd != null && passwd.length() != 0)
        {
            System.out.print("Going to see if "+userid+" can authenticate"+"\n");
            int added = 0;
            boolean existinguser = User.ExistingUser(userid);
            boolean authenticated = false;
            try {
                authenticated = User.AuthenticateUser(userid, passwd);
            } catch (NamingException e) {
                response.sendRedirect("/<app>/?error");
            }
            System.out.print("Is "+userid+" an existing user? "+existinguser+"\n");
            System.out.print(userid+" authenticated equals "+authenticated+"\n");
            if (existinguser == true)
            {
                System.out.print("passed the existing IF \n");
                if (authenticated == true)
                {                   
                    System.out.print("passed the authenticated IF \n");
                    String user = User.GetUserID(userid);
                    String role = User.GetUserRole(userid);
                    Cookie userCookie = new Cookie("user",user);
                    Cookie roleCookie = new Cookie("role", role);
                    userCookie.setMaxAge(30*60);
                    roleCookie.setMaxAge(30*60);
                    response.addCookie(userCookie);
                    response.addCookie(roleCookie);
                    System.out.print("just added the cookies \n");
                    RequestDispatcher dispatcher = request.getRequestDispatcher("/WEB-INF/index.jsp");
                    System.out.print("setup the forward \n");
                    dispatcher.forward(request, response);
                    System.out.print("WHY THE !@#$ AM I LOGGING THIS??? \n");
                }
                else
                {
                    response.sendRedirect("/<app>/?error");
                }
            }
            else
            {
                try {
                    added = User.AddToApplication(userid);
                } catch (SQLException e) {
                    response.sendRedirect("/<app>/?contactsupport");
                }
                if (added == 1)
                {
                    response.sendRedirect("/<app>/?error");
                }
                else
                {
                    response.sendRedirect("/<app>/?error");
                }
            }
        }
        else
        {
            response.sendRedirect("/<app>/?error");
        }
    }
    protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        doGet(request, response);
    }
}

---

但是，我已经移动了仪表板中的所有内容，以便由一个控制器进行预处理，该控制器正在验证用户是否仍然是用户并且他们仍然登录。将登录servlet设置为转发到仪表板的主控制器后。。一切都按计划进行。

2注释：您应该始终尝试提供原始的servlet代码；您应该尝试使用JavaEE安全性，而不是自己执行安全性，然后重定向将由容器完成。很难说你到底在做什么。我将研究如何使用JavaEE安全性。非常感谢。

Going to see if <user> can authenticate
Is <user> an existing user? true
<user> authenticated equals true
passed the existing IF 
passed the authenticated IF 
just added the cookies 
setup the forward.. goodbye! 
WHY THE HELL AM I LOGGING THIS???

<c:choose>
    <c:when test="${cookie.role.value==null}">
        <c:redirect url="${baseURL}/?what" />
    </c:when>
    <c:otherwise></c:otherwise>
</c:choose>