### Question:
MapUtils { public static boolean containsKey(Map<?, ?> map, Object key) { if (null == map) { return false; } return map.containsKey(key); }  static boolean containsKey(Map<?, ?> map, Object key); @SuppressWarnings("unchecked") static Set<String> getKeys(Map<String, Object> map, Set<String> keys); static Map<O, List<I>> sortValues(Map<O, List<I>> map, Comparator<I> comparator); static Map<O, List<I>> sortKey(Map<O, List<I>> map, Comparator<O> comparator);  }### Answer:
@Test(dataProvider = "containsKey") public void testContainsKey(Map<?, ?> map, Object key, boolean expected) { boolean actual = MapUtils.containsKey(map, key); Assert.assertEquals(actual, expected); }