I see the below stated in the servlet 3 specification:
"We emphasize that this specification is not a user’s guide for servlet developers and is not intended to be used as such. References useful for this purpose are available from http://java.sun.com/products/servlet."
If the specification is not intended as a user guide, what is ? The url they have provided is no longer valid and Iam looking for a authoritative user guide for servlets from Oracle.