Question

我正在使用Java Filter来测试身份验证。如果用户输入正确的用户ID和密码组合，则过滤器会有效地将它们转发给servlet。但是，如果输入了错误信息，则会将用户发送回他们来自的登录页面。出于某种原因，当他们被发送回登录页面时，＆＃34; login.html＆＃34;而是显示文件。以下是过滤器的代码：

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。

登录尝试失败后使用过滤器重定向

1 个答案: