private static DeterministicAead createDeterministicAead(AesSivKey key)
      throws GeneralSecurityException {
    validateParameters(key.getParameters());
    return AesSiv.create(key);
  }
This key manager generates new {@code AesSivKey} keys and produces new instances of {@code
AesSiv}.
java_src/src/main/java/com/google/crypto/tink/daead/AesSivKeyManager.java