Jetty 6 Architecture
View from 20,000 feet
The Jetty Server is the plumbing between a collection of Connectors that accept HTTP connections, and a collection of Handlers that service requests from the connections and produce responses, with the work being done by threads taken from a thread pool.
While the jetty request/responses are derived from the Servlet API, the full features of the servlet API are only available if the appropriate handlers are configured. For example, the session API on the request is inactive unless the request has been passed to a Session Handler. The concept of a Servlet itself is represented by a Servlet Handler.
Thus a Jetty server may be built using simply connectors and handlers, but without using Servlets.
Contexts are handlers that group other handlers below a particular URI context path or a virtual host. Contexts may use the base ContextHandler, the servlet Context or a Web Application Context. A web application context combines handlers for security, session and servlets in a single unit that can be configured with a web.xml descriptor.