<servlet-mapping>
<servlet-name> s1</servlet-name>
<url-pattern> /abc </url-pattern>
</servlet-mapping>
<servlet-mapping>
<servlet-name> s2</servlet-name>
<url-pattern> /abc </url-pattern>
</servlet-mapping>
<servlet-mapping>
<servlet-name> s3</servlet-name>
<url-pattern> /* </url-pattern>
</servlet-mapping>
如果有一个请求 /abc,哪个Servlet会被调用?为什么?