So I finished the Coroutines - Hands on course https://play.kotlinlang.org/hands-on/Introduction%20to%20Coroutines%20and%20Channels/05_Concurrency And the thing I don't understand is this

To run the coroutine only on the main UI thread, we should specify Dispatchers.Main as an argument:
launch(Dispatchers.Main) {
    updateResults()
}

I would have expected

Dispatchers.Swing

to be used here, it is available in the course's setup. So a) under which circumstances is

Dispatchers.Main

equal to

Dispatchers.Swing

and b) If I want to use a Dispatcher backed by a single Thread (to avoid concurrent access on some unsychronized code), if I'm in a situation where

Dispatchers.Main

is equal to

Dispatchers.Swing

, and I don't want to use the UI-Thread to be responsible, which Dispatcher do I use instead? (AFAIK

Dispatchers.Default

is backed by as many threads as the computer has Hyperthreads and

<http://Dispatchers.IO|Dispatchers.IO>

is very specific as well.) Is there something better than

Executors.newSingleThreadExecutor().asCoroutineDispatcher()

? c) assuming I'm not on the JVM (and using

Executors

is therefore not an option), what's the Kotlin Multiplatform solution to create your own

CoroutineDispatcher

with a specific thread-count?

Hi you can refer this blog I think this might clear your doubt

a) You generally don’t need to worry about that.

Dispatchers.Main

will be automatically set to whatever is appropriate for the UI framework you’re using. On the JVM, I believe it’s done via service loader (so if you depend on the swing support artifact, it will be bound to Swing) b) If you want to avoid concurrent access in coroutines, don’t create a separate dispatcher, just use a

Mutex

, a

Semaphore

, or another technique that limits concurrency (like actors). c) Multi-threaded coroutines on kotlin native is a work-in-progress without an ETA. There is a draft PR up for support here: https://github.com/Kotlin/kotlinx.coroutines/pull/1648

@Nikhil Mule I don’t work on Android at all. Currently on JVM and maybe Multiplatform in the future. @Zach Klippenstein (he/him) [MOD] sounds good, thanks