private static com.google.crypto.tink.proto.HpkeParams toProtoParameters(HpkeParameters params)
      throws GeneralSecurityException {
    return com.google.crypto.tink.proto.HpkeParams.newBuilder()
        .setKem(KEM_TYPE_CONVERTER.toProtoEnum(params.getKemId()))
        .setKdf(KDF_TYPE_CONVERTER.toProtoEnum(params.getKdfId()))
        .setAead(AEAD_TYPE_CONVERTER.toProtoEnum(params.getAeadId()))
        .build();
  }
Registers previously defined parser/serializer objects into a given registry.
java_src/src/main/java/com/google/crypto/tink/hybrid/HpkeProtoSerialization.java