Self-testing code is software that incorporates built-in tests (see test-first development).

In Java, to execute a unit test from the command line, a class can have methods like the following.

// Executing <code>main</code> runs the unit test. public static void main(String[] args) { test(); } static void test() { assert foo == bar; }

To invoke a full system test, a class can incorporate a method call.

public static void main(String[] args) { test(); TestSuite.test(); // invokes full system test }

In addition, Java has some Jupiter API libraries for self-testing code. assert can be used in various ways such as assert equals, which checks if the given variable is equal to the value given.

@Test void checkplayer() { Board board = new Board(10); board.addplayer(1); int check = board.getCurrentPlayer(1); assertEquals(1, check); }