I have created a slight variation to the Java starter package. I have covered most of the code with unit tests and refactored it a little bit. To build and start the tests, you will need JUnit.
In the package there is also a convenience class for unit testing that allows you to easily create a GameMap from a string representation. The notation is a bit cryptic, but still better than bunch of .setOwner() calls.
GameMap gameMap = GameMapFactory.create(
"A1- A1- A1-\n" +
" 2- A1- 4.\n" +
" 4+ A2- B1.");
// A - you
// B, C, D - enemies
// 0, 1, 2... 5 - different strengths
// '.', '-', '+' - different production levels
All the details are in the code and unit tests. You can clone & fork it in GitHub. All suggestions and pull requests are welcome. Enjoy!