Masters of Java (MoJ) is an open source Java programming contest environment. It allows you to hold programming contests in an easy and manageable way. MoJ consists of 3 parts :

• Server : responsible for the score, time, compiling, testing etc.
• Client : Mini development environment with an Editor, Test-Sets and a description.
• Assignments : pluggable modules which hold an assignment (or case) for the contestants to solve.

A Typical MoJ round takes 30 minutes in which the contestants have to complete the assignment and pass all the unit tests. For each second remaining a point is scored.

The origin of Masters of Java lies in a brain wave of Robert Bor, who said "We need more Java Fun here in the Netherlands" and then convinced Erik Hooijmeijer to build a gaming environment (not that he needed much convincing :-) and Klaasjan Tukker of the NLJUG to organize an event around it. It became known as "Masters of Java 2004".