@Test public void testHasUniqueObject() { List<String> list = new LinkedList<>(); list.add("myElement"); list.add("myOtherElement"); assertFalse(CollectionUtils.hasUniqueObject(list)); list = new LinkedList<>(); list.add("myElement"); assertTrue(CollectionUtils.hasUniqueObject(list)); list = new LinkedList<>(); list.add("myElement"); list.add(null); assertFalse(CollectionUtils.hasUniqueObject(list)); list = new LinkedList<>(); list.add(null); list.add("myElement"); assertFalse(CollectionUtils.hasUniqueObject(list)); list = new LinkedList<>(); list.add(null); list.add(null); assertTrue(CollectionUtils.hasUniqueObject(list)); list = new LinkedList<>(); list.add(null); assertTrue(CollectionUtils.hasUniqueObject(list)); list = new LinkedList<>(); assertFalse(CollectionUtils.hasUniqueObject(list)); }