@AccessesPartialKey
  static com.google.crypto.tink.aead.ChaCha20Poly1305Key createChaChaKey(
      ChaCha20Poly1305Parameters parameters, @Nullable Integer idRequirement)
      throws GeneralSecurityException {
    return com.google.crypto.tink.aead.ChaCha20Poly1305Key.create(
        parameters.getVariant(), SecretBytes.randomBytes(KEY_SIZE_IN_BYTES), idRequirement);
  }
This instance of {@code KeyManager} generates new {@code ChaCha20Poly1305} keys and produces new
instances of {@code ChaCha20Poly1305}.
java_src/src/main/java/com/google/crypto/tink/aead/ChaCha20Poly1305KeyManager.java