19.12. Session Tracking
This section shows you how to use the servlet session tracking API to keep track of visitors as they move around at your site.
The Need for Session Tracking
HTTP is a “stateless” protocol: each time a client retrieves a Web page, it opens a separate connection to the Web server, and the server does not automatically maintain contextual information about a client. Even with servers that support persistent (keep-alive) HTTP connections and keep a socket open for multiple client requests that occur close together in time, there is no built-in support for maintaining contextual information. This lack of context causes a number of difficulties. For example, when clients at an on-line store add an item to their shopping carts, ...