private static Prf createPrimitive(AesCmacPrfKey key) throws GeneralSecurityException {
    validate(key.getParameters());
    return PrfAesCmac.create(key);
  }
This key manager generates new {@code AesCmacKeyPrf} keys and produces new instances of {@code
AesCmacPrf}.
java_src/src/main/java/com/google/crypto/tink/prf/AesCmacPrfKeyManager.java