过滤器的高级配置

 过滤器高级拦截

2     <filter-mapping>
        <filter-name>FilterDemo3</filter-name>
        <url-pattern>/*</url-pattern>
        <dispatcher>REQUEST</dispatcher> 默认情况。如果写了另外一种情况，默认的就没有了
        <dispatcher>FORWARD</dispatcher>
        <dispatcher>INCLUDE</dispatcher>
        <dispatcher>ERROR</dispatcher>
      </filter-mapping>