Building

The code can be compiled, unit tests run, and packaged into a .JAR file using Maven.

Additions to the specification

Accepts 3 optional command line arguments

• --ansi - use colored output on ANSI compatible terminals
• --big - play on a 15x12 board
• --tiny - play on a 5x5 board

Assumptions

• With no mention of what to do after a round, the program exits after a win
• The code requires no external libraries to run, but JUnit is required for tests
• It is written to show maintainable, extensible code rather than how I would implement it for a one-off or well-scoped project. So it has:
  • Interfaces with only one implementation
  • Methods that could be inlined, but exist for legibility
• The Java language level was kept low deliberately, avoiding lambdas, newer APIs etc.