Java is built upon it's community :), look no further: https://github.com/Randgalt/record-builder, although hiding the constructor behind the builder is not something I am sure supported by that library

I also remember a discussion in the mailing list about withers: https://mail.openjdk.org/pipermail/amber-spec-experts/2020-M...

Not sure where it stands now, you can ask in the mailing list about this