@Test
  public void testCreateMasterKeyNoSalt()
      throws InvalidKeySpecException, NoSuchAlgorithmException, NoSuchProviderException {
    SaltedSecretKey masterKeyForPasswordTestNoSalt1 = CipherUtil.createMasterKey("Test");
    SaltedSecretKey masterKeyForPasswordTestNoSalt2 = CipherUtil.createMasterKey("Test");

    logger.log(Level.INFO, "Key comparison for password 'Test':");
    logger.log(
        Level.INFO,
        "- Master key 1: " + StringUtil.toHex(masterKeyForPasswordTestNoSalt1.getEncoded()));
    logger.log(
        Level.INFO,
        "     with salt: " + StringUtil.toHex(masterKeyForPasswordTestNoSalt1.getSalt()));
    logger.log(
        Level.INFO,
        "- Master key 2: " + StringUtil.toHex(masterKeyForPasswordTestNoSalt2.getEncoded()));
    logger.log(
        Level.INFO,
        "     with salt: " + StringUtil.toHex(masterKeyForPasswordTestNoSalt2.getSalt()));

    assertFalse(
        Arrays.equals(
            masterKeyForPasswordTestNoSalt1.getSalt(), masterKeyForPasswordTestNoSalt2.getSalt()));
    assertFalse(
        Arrays.equals(
            masterKeyForPasswordTestNoSalt1.getEncoded(),
            masterKeyForPasswordTestNoSalt2.getEncoded()));
  }
  @Test
  public void testCreateMasterKeyWithSalt()
      throws InvalidKeySpecException, NoSuchAlgorithmException, NoSuchProviderException {
    long timeStart = System.currentTimeMillis();

    SaltedSecretKey masterKeyForPasswordTestAndSalt123 =
        CipherUtil.createMasterKey("Test", new byte[] {1, 2, 3});

    long timeEnd = System.currentTimeMillis();
    long timeDuration = timeEnd - timeStart;

    logger.log(Level.INFO, "Creating master key took " + timeDuration + "ms:");
    logger.log(
        Level.INFO,
        " - Key:  " + StringUtil.toHex(masterKeyForPasswordTestAndSalt123.getEncoded()));
    logger.log(
        Level.INFO, " - Salt: " + StringUtil.toHex(masterKeyForPasswordTestAndSalt123.getSalt()));

    assertEquals("010203", StringUtil.toHex(masterKeyForPasswordTestAndSalt123.getSalt()));
    assertEquals(
        "44fda24d53b29828b62c362529bd9df5c8a92c2736bcae3a28b3d7b44488e36e246106aa5334813028abb2048eeb5e177df1c702d93cf82aeb7b6d59a8534ff0",
        StringUtil.toHex(masterKeyForPasswordTestAndSalt123.getEncoded()));

    assertEquals(
        CipherUtil.MASTER_KEY_SIZE / 8, masterKeyForPasswordTestAndSalt123.getEncoded().length);
    assertEquals("PBKDF2WithHmacSHA1", masterKeyForPasswordTestAndSalt123.getAlgorithm());
    assertEquals("RAW", masterKeyForPasswordTestAndSalt123.getFormat());

    assertTrue(timeDuration > 5000);
  }
  @Test
  public void testCreateDerivedKeys()
      throws InvalidKeySpecException, NoSuchAlgorithmException, NoSuchProviderException {
    SaltedSecretKey masterKey = createDummyMasterKey();
    CipherSpec cipherSpec = CipherSpecs.getCipherSpec(CipherSpecs.AES_128_GCM);

    byte[] derivedKeySalt1 = new byte[] {1, 2, 3};
    byte[] derivedKeySalt2 = new byte[] {1, 2, 3, 4};

    SaltedSecretKey derivedKey1 =
        CipherUtil.createDerivedKey(masterKey, derivedKeySalt1, cipherSpec);
    SaltedSecretKey derivedKey2 =
        CipherUtil.createDerivedKey(masterKey, derivedKeySalt2, cipherSpec);

    logger.log(Level.INFO, "- Derived key 1: " + StringUtil.toHex(derivedKey1.getEncoded()));
    logger.log(Level.INFO, "      with salt: " + StringUtil.toHex(derivedKey1.getSalt()));
    logger.log(Level.INFO, "- Derived key 2: " + StringUtil.toHex(derivedKey2.getEncoded()));
    logger.log(Level.INFO, "      with salt: " + StringUtil.toHex(derivedKey2.getSalt()));

    assertEquals(128 / 8, derivedKey1.getEncoded().length);
    assertEquals(128 / 8, derivedKey2.getEncoded().length);
    assertFalse(Arrays.equals(derivedKey1.getSalt(), derivedKey2.getSalt()));
    assertFalse(Arrays.equals(derivedKey1.getEncoded(), derivedKey2.getEncoded()));
  }