Java 8 + Nashorn Scripting + Mustache = Static Page Generator
SPG is simple:
input.json + input.htm (processed by https://github.com/janl/mustache.js template) =>
SPG relies on mustache.js for rendering and therefore comes with support for sections, functions, conditional rendering etc.
SPG was created to maintain the registration pages for http://workshops.adam-bien.com (externalize the dates, show badges like "registration closed"), so it is heavily used in production :-).
You will find sources at github. SPG is open source and Apache 2 licensed.
See you at Java EE Workshops at MUC Airport. SPG is going to be discussed during the Java EE 7 + HTML 5 workshop.