### Question:
Hash { public static String keccak256(String hex) { byte[] bytes = NumericUtil.hexToBytes(hex); byte[] result = keccak256(bytes); return NumericUtil.bytesToHex(result); }  static String keccak256(String hex); static byte[] keccak256(byte[] input); static byte[] generateMac(byte[] derivedKey, byte[] cipherText); static String sha256(String hexInput); static byte[] sha256(byte[] input); static byte[] hmacSHA256(byte[] key, byte[] data); static byte[] merkleHash(byte[] oriData);  }### Answer:
@Test public void testKeccak256() { for (String[] example : SHA3Example) { assertEquals(example[1], Hash.keccak256(example[0])); } }