Stan,
There are different ways to interpret your question.
The contents of POST parameters are URL Encoded. This is a simple process
See class java.net.URLEncoder. Sometimes parts of the header are Base64 encoded.
If you mean the general encoding of a web request, I have two suggestions.
First code a socket program to listen to port 80 (or the port of your choice, if you specify a different port from your browser) and to display what ever contents is sent to it. It will show a lot. Send it get, post, multipart form, etc. requests from your browser and you can see how they are formatted.
As far as reading material, I would suggest a book on CGI. The PERL or C code shows a lot about how requests are formatted. Apache/CGI does less "hand holding" than a
servlet engine like
Tomcat. I would recommend the book I use, but it is a little dated. I have used it for many years, good but there are now better ones out there. Maybe someone can recommend one or you can check the Amazon customer reviews.
Not exactly what you are looking for, but I hope it helps....
Don :roll: