5.1. Servlet Equivalent of CGI Variables
For each standard CGI variable, this section summarizes its purpose and the means of accessing it from a servlet. As usual, once you are familiar with this information, you may want to use Appendix A (Servlet and JSP Quick Reference) as a reminder. Assume request is the HttpServletRequest supplied to the doGet and doPost methods.
If an Authorization header was supplied, this variable gives the scheme specified (basic or digest). Access it with request.getAuthType().
For POST requests only, this variable stores the number of bytes of data sent, as given by the Content-Length request header. Technically, since the CONTENT_LENGTH CGI variable is a string, the servlet equivalent is