@Test public void test() { ArrayList<Box> set = new ArrayList<Box>(); set.add(new Box(0, 0, 1, 1)); set.add(new Box(1, 1, 2, 2)); Collection<Box> r = BoxStrategy.optimalPart(3, set); assertEquals(2, r.size()); for (Box b : r) { assertEquals(1, b.size(), 0.000000001); } }