1.过滤应用程序中所有资源： 

<filter> 
    <filter-name>loggerfilter</filter-name> 
    <filter-class>myfilter.LoggerFilter</filter-class> 
</filter> 
<filter-mapping> 
    <filter-name>loggerfilter</filter-name> 
    <url-pattern>/*</url-pattern> 
</filter-mapping> 

2.过滤指定的类型文件资源 

<filter> 
    <filter-name>loggerfilter</filter-name> 
    <filter-class>myfilter.LoggerFilter</filter-class> 
</filter> 
<filter-mapping> 
    <filter-name>loggerfilter</filter-name> 
    <url-pattern>*.html</url-pattern> 
</filter-mapping> 

其中<url-pattern>*.html</url-pattern>要过滤jsp那么就改*.html为*.jsp,但是注意没有“/”斜杠 

如果要同时过滤多种类型资源： 

<filter> 
    <filter-name>loggerfilter</filter-name> 
    <filter-class>myfilter.LoggerFilter</filter-class> 
</filter> 
<filter-mapping> 
    <filter-name>loggerfilter</filter-name> 
    <url-pattern>*.html</url-pattern> 
</filter-mapping> 

<filter-mapping> 
    <filter-name>loggerfilter</filter-name> 
    <url-pattern>*.jsp</url-pattern> 
</filter-mapping> 

3.过滤指定的目录 

<filter> 
    <filter-name>loggerfilter</filter-name> 
    <filter-class>myfilter.LoggerFilter</filter-class> 
</filter> 
<filter-mapping> 
    <filter-name>loggerfilter</filter-name> 
    <url-pattern>/folder_name/*</url-pattern> 
</filter-mapping> 

4.过滤指定的servlet 

<filter> 
    <filter-name>loggerfilter</filter-name> 
    <filter-class>myfilter.LoggerFilter</filter-class> 
</filter> 
<filter-mapping> 
    <filter-name>loggerfilter</filter-name> 
    <servlet-name>loggerservlet</servlet-name> 
</filter-mapping> 
<servlet> 
    <servlet-name>loggerservlet</servlet-name> 
    <servlet-class>myfilter.LoggerServlet</servlet-class> 
</servlet> 

5.过滤指定文件 

<filter> 
    <filter-name>loggerfilter</filter-name> 
    <filter-class>myfilter.LoggerFilter</filter-class> 
</filter> 
<filter-mapping> 
    <filter-name>loggerfilter</filter-name> 
    <url-pattern>/simplefilter.html</url-pattern> 
</filter-mapping> 

<filter-mapping>

______________________________________ <filter-mapping> filter-mapping 元素的两个主要子元素filter-name和url-pattern.用来定义Filter所对应的URL. <filter-name>Filter的名称</filter-name> 定义Filter的名称. <url-pattern>URL</url-pattern> Filter所对应的RUL.例如:<url-pattern>/Filter/Hello</url-pattern>

<servlet-name>Servlet的名称<servlet-name>

定义servlet的名称. <dispatcher>REQUEST|INCLUDE|FORWARD|ERROR</disaptcher> 设定Filter对应的请求方式,有RQUEST,INCLUDE,FORWAR,ERROR四种,默认为REQUEST. </filter-mapping> 范例: <filter-mapping>    <filter-name>GZIPEncoding</filter-name>    <url-pattern>/*</url-pattern> </filter-mapping>