private void validateKey(AesSivKey key) throws GeneralSecurityException {
    if (key.getKeyValue().size() != KEY_SIZE_IN_BYTES) {
      throw new InvalidKeyException(
          "Invalid key size: "
              + key.getKeyValue().size()
              + ". Valid keys must have "
              + KEY_SIZE_IN_BYTES
              + " bytes.");
    }
  }
Custom type url that this manager does support.
java_src/src/main/java/com/google/crypto/tink/daead/internal/testing/LegacyAesSivTestKeyManager.java