java - 使用过滤器在登录尝试失败后重定向

Question

我正在使用 Java 过滤器来测试身份验证。如果用户输入正确的用户 ID 和密码组合，过滤器就会有效地将它们转发到 servlet。但是，如果输入了错误的信息，则用户将被发送回他们原来的登录页面。由于某种原因，当它们被发送回登录页面时，会显示“login.html”文件的代码。这是过滤器的代码:

package com.simpleServletDemo;

import java.io.IOException;
import java.io.PrintWriter;
import javax.servlet.*;
import javax.servlet.annotation.WebFilter;

/**
 *
 * @author Not Important
 */
@WebFilter("/MyFilterChecker")
public class MyFilterChecker implements Filter {


    public void doFilter(ServletRequest request, ServletResponse response,
            FilterChain chain)
            throws IOException, ServletException {

        String userID = request.getParameter("txtUser");
        String password = request.getParameter("txtPassword");

        PrintWriter out = response.getWriter();

        if (userID.equals("notimpotant@gmail.com") && password.equals("password12345")) {
            out.print("Success!");
            chain.doFilter(request, response); //Sends Request and response to next resource
        } else {
            out.print("Incorrect Username or Password!");
            RequestDispatcher dispatcher = request.getRequestDispatcher("login.html");
            dispatcher.include(request, response);
        }
    }


    public void destroy() {        
    }


    public void init(FilterConfig filterConfig) {        

    }
}

我哪里出错了？谢谢!

我还包含了 web.xml 文件来显示映射:

<?xml version="1.0" encoding="UTF-8"?>
<web-app version="3.1" xmlns="http://xmlns.jcp.org/xml/ns/javaee" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee http://xmlns.jcp.org/xml/ns/javaee/web-app_3_1.xsd">
    <servlet>
        <servlet-name>MyLoginServlet</servlet-name>
        <servlet-class>com.simpleServletDemo.MyLoginServlet</servlet-class>
    </servlet>
    <servlet-mapping>
        <servlet-name>MyLoginServlet</servlet-name>
        <url-pattern>/Login</url-pattern>
    </servlet-mapping>
    <filter>
        <filter-name>MyFilterChecker</filter-name>
        <filter-class>com.simpleServletDemo.MyFilterChecker</filter-class>
    </filter>
    <filter-mapping>
        <filter-name>MyFilterChecker</filter-name>
        <url-pattern>/Login</url-pattern>  
    </filter-mapping>
 </web-app>

Answer 1

将您的dispatcher.include()方法更改为dispatcher.forward()方法。您还可以使用response.redirect()方法转发到login.html文件。