@Override
  public Aead getAead(String keyUri) throws GeneralSecurityException {
    checkCredentials();
    String keyset = stripPrefix(prefix, keyUri);
    return TinkJsonProtoKeysetFormat.parseKeyset(keyset, InsecureSecretKeyAccess.get())
        .getPrimitive(Aead.class);
  }
A client for testing.

<p>The client supports all key uris which start with "tinkey-test-kms-client://" followed by a
JSON-encoded AEAD keyset. It will use this Aead when "getAead" is called. As credentials, it must
be given a file which starts whose contents are "VALID CREDENTIALS".
tools/tinkey/src/main/java/com/google/crypto/tink/tinkey/TinkeyTestKmsClient.java