编码过滤器

1、编码过滤器filter必须配置在web.xml中的第一个，org.springframework.web.filter.CharacterEncodingFilter

<filter>
    <filter-name>CharacterEncodingFilter</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>CharacterEncodingFilter</filter-name>
    <url-pattern>/*</url-pattern>
</filter-mapping>