@Test
public void testUnsealECV2WithCustomKem() throws Exception {

  PaymentMethodTokenRecipient recipient =
      new PaymentMethodTokenRecipient.Builder()
          .protocolVersion(PaymentMethodTokenConstants.PROTOCOL_VERSION_EC_V2)
          .senderVerifyingKeys(GOOGLE_VERIFYING_PUBLIC_KEYS_JSON)
          .recipientId(RECIPIENT_ID)
          .addRecipientKem(
              new MyPaymentMethodTokenRecipientKem(MERCHANT_PRIVATE_KEY_PKCS8_BASE64))
          .build();
  assertEquals(PLAINTEXT, recipient.unseal(sealECV2(PLAINTEXT)));
}