I would like to add a new contributed plugin.
The Github repository is https://github.com/sheepdalton/moodle-filter-java-embed

This filter permits you to embed Java code into your lesson. This is ideal if you want to build a course teaching computer science in the style of http://www.codecademy.com

It does this by converting the java to javascript then interpreting the javascript (uses Processing_JS as engine to do this). To use this you will have to have java script enabled.