### Question:
Util { public static boolean contains(Map<String, ?> x, Map<String, ?> y, String[] keys) { for (String key : keys) { if (!x.get(key).equals(y.get(key))) return false; } return true; } private  Util(); static boolean contains(Map<String, ?> x, Map<String, ?> y, String[] keys); static String concatenate(Map<String, Object> map, String[] keys, String delimiter); static Map<String, Object> parseJson(String json); static String getUniqueID(String idstring); static String getStackTrace(Exception e); static String base64Decode(String encodedStr); static String encodeUrl(String toBeEncoded); static String base64Encode(String str); static Map<String,Object> getHeader(String base64Creds); static List<Map<String, T>> fetchDataFromS3(String s3Account,String s3Region,String s3Role, String bucketName,String path); static List<String> retrieveErrorRecords(String responseStr);  }### Answer:
@Test public void testContains() { HashMap<String, String> hash1 = new HashMap<>(); HashMap<String, String> hash2 = new HashMap<>(); hash2.put("foo", "3"); Assert.assertFalse(Util.contains(hash2, hash1, new String[]{"foo"})); hash1.put("foo", "3"); Assert.assertTrue(Util.contains(hash2, hash1, new String[]{"foo"})); }