### Question:
UuidUtil { public static boolean isValidUUID(String uuid) { return !StringUtils.isEmpty(uuid) && UUID_PATTERN.matcher(uuid).matches(); } private  UuidUtil(); static String insertHyphens(String uuidWithoutHyphens); static String stripHyphens(String uuid); static boolean isValidUUID(String uuid);  }### Answer:
@Test public void isValidUuidTest() { Assert.assertFalse(UuidUtil.isValidUUID("9aa395cb8e914e77aeaf1a41d85bffa8")); Assert.assertFalse(UuidUtil.isValidUUID("9AA395CB-8E91-4E77-AEAF-1A41D85BFFA8")); Assert.assertTrue(UuidUtil.isValidUUID("00000000-0000-0000-0000-000000000000")); Assert.assertTrue(UuidUtil.isValidUUID("9aa395cb-8e91-4e77-aeaf-1a41d85bffa8")); }