比如struts,一般都配置
<filter>
    <filter-name>decodeservlet</filter-name>
    <filter-class>com.csdn.DecodeServlet</filter-class>
    <init-param>
      <param-name>charset</param-name>
      <param-value>GBK</param-value>
    </init-param>
  </filter>
来转换编码而使用AjaxAnywhere的时候,再配置
  <filter>
        <filter-name>AjaxAnywhere</filter-name>
        <filter-class>org.ajaxanywhere.AAFilter</filter-class>
    </filter>
     <filter-mapping>
        <filter-name>AjaxAnywhere</filter-name>
        <url-pattern>*.do</url-pattern>
    </filter-mapping>
  </filter>当web.xml使用过多的filter会影响性能吗?