I\'m trying to create a web user interface for a Java application. The user interface is going to be very simple, consisting of a single page with a form for users to pose t
Jetty is a very lightweight container, and perfect for your development scenario.
You might want to look at Wicket for your rendering side; you seem more comfortable doing code-like tasks as opposed to straight UI.
The pattern you are describing is the Singleton pattern. Take a look at the google results for singleton in java.