This package contains Servlets that implement some of the standard functionality provided by the Catalina servlet container. Because these servlets are in the org.apache.catalina package hierarchy, they are in the privileged position of being able to reference internal server data structures, which application level servlets are prevented from accessing (by the application class loader implementation).

To the extent that these servlets depend upon internal Catalina data structures, they are obviously not portable to other servlet container environments. However, they can be used as models for creating application level servlets that provide similar capabilities -- most obviously the DefaultServlet implementation, which serves static resources when Catalina runs stand-alone.