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Comment by bcrosby95 | Hacker News Reader

I would use records a lot more (pretty much everywhere) if I could easily derive new values from existing ones.

There are some funny ways to work with records. I can recommend this article: https://benjiweber.co.uk/blog/2020/09/19/fun-with-java-recor...

Still way too much typing compared to lombok's @Value @With.

This will be solved[1]:

record Point(int x, int y) {}

Point p = new Point(1, 2); Point pp = p with { x = 3; }

[1] https://github.com/openjdk/amber-docs/blob/master/eg-drafts/...

Interesting. It's ok. It seems like they're adding this syntax just to avoid extra copies eg, `p with {x = 3, y = 4}` instead of `p.withX(3).withY(4)`. I really don't mind the later.

My gut feel is that records break encapsulation and will make refactoring slightly more difficult than the equivalent lombok value class. But if this gets more people making objects immutable, I'm all for it.

The perfect transparency of the underlying data is rather the whole point of records. Tempered by immutability, records should be a useful tool for modeling data where encapsulation is not required. Note that it is still possible to add methods that can perform computation on the underlying data.

TBH both approaches are just poor design of the object model. The one from my link is a clever but inefficient way to manipulate records (reflection), the one with Lombok is creating redundant interfaces without business meaning. A record with few business methods is lean enough and ensures that only valid transitions can happen.

Eh? This is pretty good:

   Colour changed = colour.withRed(5);

Every method of your API must serve some business purpose. "With" methods and setters generated or written "just in case" often do not have one or they are being used only in tests, which would be insufficient justification for having them. Does your code really need to change individual components of the color? If it is not a graphic editor, probably not and those methods will be redundant.

That sounds unpleasantly pedantic.

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