关于java过滤器的问题

应该是Web.XML的问题我把下面的那段东东加上去他就报错，运行页面就报404错误

<filter>
<filter-name>CheckFilter</filter-name>
<filter-class>ch02.filter.CheckFilter</filter-class>
<init-param>
<param-name>first</param-name>
<param-value>8</param-value>
</init-param>
<init-param>
<param-name>last</param-name>
<param-value>20</param-value>
</init-param>
</filter>
<filter-mapping>
<filter-name>CheckFilter</filter-name>
<url-pattern>/y2144/*</url-pattern>
<dispatcher>REQUEST</dispatcher>
<dispatcher>FORWARD</dispatcher>
</filter-mapping>

错误：2009-10-21 19:49:53 org.apache.catalina.core.StandardContext start
严重: Error filterStart
2009-10-21 19:49:53 org.apache.catalina.core.StandardContext start
严重: Context [/restrant] startup failed due to previous errors
2009-10-21 19:49:53 org.apache.coyote.http11.Http11Protocol start

当我把他删掉之后，一切正常。请高手帮忙，这是为什么？，怎么解决？

问陈名喜就好了！

<filter>
<filter-name>CheckFilter</filter-name>
<filter-class>ch02.filter.CheckFilter</filter-class>
<init-param>
<param-name>encoding</param-name>
<param-value>UTF-8</param-value>
</init-param>
</filter>
<filter-mapping>
<filter-name>CheckFilter</filter-name>
<url-pattern>/y2144/*</url-pattern>
<dispatcher>REQUEST</dispatcher>
<dispatcher>FORWARD</dispatcher>
</filter-mapping>

试一下改为这样: <filter> <filter-name>CheckFilter</filter-name> <filter-class>ch02.filter.CheckFilter</filter-class> <init-param> <param-name>encoding</param-name> <param-value>UTF-8</param-value> </init-param> </filter> <filter-mapping> <filter-name>CheckFilter</filter-name> <url-pattern>/y2144/*</url-pattern> <dispatcher>REQUEST</dispatcher> <dispatcher>FORWARD</dispatcher> </filter-mapping>