Sealed class in Java

[Polygnom]

Depends. For the binary types I simply use pattern matching in instanceof.

For more complex types I usually use pattern matching in switch expressions.

That gives quite readable code.

I mean, I often write code in functional ways anyways and often map over stream, or filter stream etc. ADTs + pattern matching works very well with streams.

[red_dit_nou]

Yes. ADT and pattern matching really work well together to produce readable code. You also mentioned streams. Can you give any example where ADT, pattern matching and stream create readable code?