@AccessesPartialKey
  static com.google.crypto.tink.aead.XChaCha20Poly1305Key createXChaChaKeyFromRandomness(
      XChaCha20Poly1305Parameters parameters,
      InputStream stream,
      @Nullable Integer idRequirement,
      SecretKeyAccess access)
      throws GeneralSecurityException {
    return com.google.crypto.tink.aead.XChaCha20Poly1305Key.create(
        parameters.getVariant(),
        Util.readIntoSecretBytes(stream, KEY_SIZE_IN_BYTES, access),
        idRequirement);
  }
This instance of {@code KeyManager} generates new {@code XChaCha20Poly1305} keys and produces new
instances of {@code XChaCha20Poly1305}.
java_src/src/main/java/com/google/crypto/tink/aead/XChaCha20Poly1305KeyManager.java