filter 过滤器

<!--配置过滤器-->
	<filter>
		<filter-name>MergeFilter</filter-name>
		<filter-class>com.commons.filter.MergeFilter</filter-class>
	</filter>

	<!--映照过滤器-->
	<filter-mapping>
		<filter-name>MergeFilter</filter-name>
		<url-pattern>/selfhelp/*</url-pattern>
		<dispatcher>REQUEST</dispatcher>  
		<dispatcher>FORWARD</dispatcher>
		<dispatcher>ERROR</dispatcher>
		<dispatcher>INCLUDE</dispatcher>
	</filter-mapping><!--配置过滤器-->
	<filter>
		<filter-name>MergeFilter