JCF를 이용한 집합 연산 단위 테스트

public class SetTest3 { private static final Integer[] UNION = {1, 2, 3, 4, 5}; private static final Integer[] INTERSECTION = {3}; private static final Integer[] DIFFERENCES = {1, 2}; private Set<Integer> a; private List<Integer> b; @Before public void setUp(){ a = new HashSet<Integer>(Arrays.asList(1, 2, 3)); b = Arrays.asList(3, 4, 5); } @Test public void test_합집합() { a.addAll(b); assertArrayEquals(UNION, a.toArray()); } @Test public void test_차집합(){ a.removeAll(b); assertArrayEquals(DIFFERENCES, a.toArray()); } @Test public void test_교집합(){ a.retainAll(b); assertArrayEquals(INTERSECTION, a.toArray()); } }