The rules for servlet mappings are covered in the Servlet 3.0 specs:
Specification of Mappings
In the Web application deployment
descriptor, the following syntax is
used to define mappings:
- A string beginning with a
/
character and ending with a /*
suffix is used for path mapping.
- A string beginning with a
*.
prefix is used as an extension
mapping.
- The empty string ("") is a special URL pattern that exactly maps to the
application's context root, i.e.,
requests of the form
http://host:port/<contextroot>/
. In
this case the path info is /
and the
servlet path and context path is empty
string ("").
- A string containing only the
/
character indicates the "default"
servlet of the application. In this
case the servlet path is the request
URI minus the context path and the
path info is null.
- All other strings are used for exact matches only.
When you encounter this error, check your web.xml and any mapping annotations (WebServlet, WebFilter, etc.)
You can find recommendations for JSF servlet mapping in the JSF 2.0 spec.
When using extension mapping the
following mapping is recommended, but
not required:
<servlet-mapping>
<servlet-name> faces-servlet-name </servlet-name>
<url-pattern>*.faces</url-pattern>
</servlet-mapping>