怎么设置了过滤器还是有乱码？

设置了字符过滤的代码，怎么还是有乱码？

package com.imooc.bbs.global;

import javax.servlet.*;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;

public class EncodingFilter implements Filter {
    private String encoding = "UTF-8";

public void init(FilterConfig filterConfig) throws ServletException {
 /* 判断一下配置文件中有没有设置编码格式
          如果有，则使用配置的
          如果没有，则使用默认值UTF-8*/
        if (filterConfig.getInitParameter("encoding") != null) {
            encoding=filterConfig.getInitParameter("encoding");
}
    }

    public void doFilter(ServletRequest req, ServletResponse res, FilterChain chain) throws IOException, ServletException {

        HttpServletRequest request = (HttpServletRequest) req;
HttpServletResponse response = (HttpServletResponse) res;
/* 设置request和response的编码格式，并放行访问链接*/
        request.setCharacterEncoding(encoding);
response.setCharacterEncoding(encoding);
        chain.doFilter(request,response);


}

    public void destroy() {

    }
}

<?xml version="1.0" encoding="UTF-8"?>

<web-app 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"
         version="3.1">

    <display-name>Archetype Created Web Application</display-name>

    <!--配置字符过滤器-->
    <filter>
        <filter-name>encoding</filter-name>
        <filter-class>com.imooc.bbs.global.EncodingFilter</filter-class>
        <init-param>
            <param-name>encoding</param-name>
            <param-value>utf-8</param-value>
        </init-param>
    </filter>
    <filter-mapping>
        <filter-name>encoding</filter-name>
        <url-pattern>/*</url-pattern>
    </filter-mapping>

    <!--    配置默认servlet，对静态资源进行处理-->
    <servlet-mapping>
        <servlet-name>default</servlet-name>
        <url-pattern>/assets/*</url-pattern>
        <url-pattern>/js/*</url-pattern>
        <url-pattern>/vendor/*</url-pattern>
        <url-pattern>*.js</url-pattern>
        <url-pattern>*.jpg</url-pattern>
        <url-pattern>*.gif</url-pattern>
        <url-pattern>*.png</url-pattern>
        <url-pattern>*.css</url-pattern>
    </servlet-mapping>
    <!--    配置springMVC的全局servlet-->
    <servlet>
        <servlet-name>SpringMVC</servlet-name>
        <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
        <init-param>
            <param-name>contextConfigLocation</param-name>
            <param-value>classpath:spring-web.xml</param-value>
        </init-param>
    </servlet>
    <servlet-mapping>
        <servlet-name>SpringMVC</servlet-name>
        <url-pattern>/</url-pattern>
    </servlet-mapping>
</web-app>

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