private static byte[] toNonNullableByteArray(byte[] data) {
    if (data == null) {
      return EMPTY_BYTE_ARRAY;
    } else {
      return data;
    }
  }
An HTTP-based client to communicate with Google Cloud KMS.
java_src/src/main/java/com/google/crypto/tink/integration/gcpkms/GcpKmsAead.java