Hi all. I want to use my immutable kotlin data cla...

# getting-started

[Gasan]

Hi all. I want to use my immutable kotlin data class in tests in my java code. In tests I initialize my data class with different values. In java I cannot use default parameters of the copy method. Also it seems to me too expensive to create multiple copies of the object while initializing it: each modification produces a new value.

Ideally, I would like to use a builder to generate the object I need. Are there any tools to automatically create such a builder from an immutable data class or do I have to write it myself?

edit: essentially to generate a "mutable" version of my data class.

[ephemient]

yeah there's several, search for them

[ephemient]

I made https://github.com/ephemient/builder-generator a long time ago, didn't maintain it

[ephemient]

GitHub search finds https://github.com/beatgrid/kodeforge which looks more recent

[Gasan]

thanks. In fact the builder itself is not needed. The only thing needed is to generate essentially a duplicate of the immutable data class but with all fields mutable.

[Gasan]

then later I can use apply kotlin function to modify the object

[Gasan]

Well, the builder is needed. But those methods to change individual fields not.

[ephemient]

https://github.com/kopykat-kt/kopykat then

[Gasan]

Something like:

MyDataBuilder().apply{ /*.. modify builder properties here */ }.build()

[Gasan]

thanks