SpringMVC配置自定义过滤器

环境

• 开发工具: idea2019.3.5
• springmvc版本: 5.1.9.RELEASE

<dependency>
   <groupId>org.springframework</groupId>
    <artifactId>spring-webmvc</artifactId>
    <version>5.1.9.RELEASE</version>
</dependency>

第一种方式: 手写过滤器进行配置 注意Filter接口是servlet里面的

• 书写过滤器类
  关于乱码过滤器类, 可以在百度更详细的大神写的乱码过滤器,该处只是简易教授配置过滤器的demo

import org.springframework.stereotype.Component;

import javax.servlet.*;
import java.io.IOException;

/**
 * 手写简易编码过滤器,用于解决post请求的中文编码乱码问题
 * @author suncp
 * @date 2020/11/29 23:21
 */
@Component
public class EncodingFilter implements Filter {

    @Override
    public void init(FilterConfig filterConfig) throws ServletException {}

    @Override
    public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException {
        servletRequest.setCharacterEncoding("UTF-8");
        servletRequest.setCharacterEncoding("UTF-8");
        filterChain.doFilter(servletRequest, servletResponse);
    }

    @Override
    public void destroy() {}
}

• 将手写的过滤器配置到web.xml中

 <!--自定义过滤器解决乱码问题-->
    <filter>
        <filter-name>encoding</filter-name>
        <filter-class>com.suncp.filter.EncodingFilter</filter-class>
    </filter>
    <filter-mapping>
        <filter-name>encoding</filter-name>
        <!--/* 可以把jsp页面也加载进去,否则只能过滤请求-->
        <url-pattern>/*</url-pattern>
    </filter-mapping>

第二种方式: 使用springMVC自带的过滤器类

• 直接配置到web.xml中, 类已经存在mvc包中(CharacterEncodingFilter)
• 关于CharacterEncodingFilter, 实际上继承多个抽象类, 根本上是实现了Filter接口

 <!--配置SpringMVC的乱码过滤 - 使用SpringMVC自带的过滤器-->
 <filter>
     <filter-name>encoding</filter-name>
     <filter-class>org.springframework.web.filter.CharacterEncodingFilter</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>

继承关系: