Hey guys! I have an implementation doubt, may be you can help me: I have a shared single common clas...

# multiplatform

[gmazzo]

Hey guys! I have an implementation doubt, may be you can help me:
I have a shared single common class that internally holds a MutableMap, so:
For JVM: I use the ConcurrentHashMap class
For Web: I use just a mutableMapOf
But for Native, I have to freeze() the singleton to avoid the IncorrectDereferenceException. So, if the whole graph is frozen, I don’t know how to have a MutableMap inside it.
Any tips?

[Arkadii Ivanov]

Hey, checkout https://github.com/touchlab/Stately

[Arkadii Ivanov]

But I don't think it will be thread safe (like ConcurrentHashMap), not sure

[Arkadii Ivanov]

You can also use something like AtomicReference<Map>, then you will be able to update and iterate concurrently.

[kpgalligan]

If you can wait for 1.3.70, there’s a new stately thing. Thread-isolated mutability! Way faster than the original stately collections. https://github.com/touchlab/Stately/blob/kpg/iso_state/stately-iso-collections/src/commonMain/kotlin/co/touchlab/stately/collections/IsoMutableMap.kt

[kpgalligan]

Current stately collections are thread safe, but are implemented with AtomicReference, so they’re not great performance-wise

[gmazzo]

Thanks! I’ll take at look at that library.
For now, I’ve drafted this class, and seems to work well (except for entries, keys and values collections), but I’m not using it

Untitled

[gmazzo]

I’ll definitely give a try on frozenHashMap 💪

[gmazzo]

@kpgalligan is it possible you lack of a js target for that platform? It’s failing to resolve for that target :(

[Arkadii Ivanov]

Yeah, no JS for stately-collections

[kpgalligan]

There was a reason but I don’t recall offhand

[gmazzo]

Browsers are single threaded maybe? The thing is that without it I can’t use this library, at least not without a simple dependency on commonMain 😞

[russhwolf]

Testing issues according to this comment https://github.com/touchlab/Stately/blame/05758c76b43ac7eb58027d60efe043f75c50273e/stately-collections/build.gradle#L82

[kpgalligan]

Had nothing to do with single threaded. I haven’t looked at it much in recent times because it’s always been on the list of things that was going to get a refactor.

[kpgalligan]

Published a quick release with js. Version number 0.9.6.1. Haven’t actually tried it in JS, but the artifact should be there soon-ish