配置spring的CharacterEncodingFilter（编码过滤器）

  <filter>

      <filter-name>encodingFilter</filter-name>

      <filter-class>org.springframework.web.filter.CharacterEncodingFilter</filter-class>

<!—初始化传入的参数 -- >

      <init-param>

             <param-name>encoding</param-name>

             <param-value>utf-8</param-value>

      </init-param>

  </filter>

  <filter-mapping>

      <filter-name>encodingFilter</filter-name>

      <url-pattern>/*</url-pattern>

  </filter-mapping>