Hands-On Design Patterns with Kotlin

Understanding contexts

To understand different contexts, let's look at the following code:

val r1 = async(Unconfined) {    for (i in 1..1000) {        println(Thread.currentThread().name)        delay(1)    }}r1.await()

Instead of yield(), we're using the delay() function, which also suspends the current coroutine.

But the output compared to yield() is different:

mainkotlinx.coroutines.DefaultExecutor...

After calling delay() for the first time, the coroutine has switched context, and as a result, threads.

For that reason, using Unconfined is not recommended for CPU-intensive tasks or tasks that need to run on a particular thread, such as UI rendering.

You can also create your own thread pool for coroutines to run on:

val pool = newFixedThreadPoolContext(2, ...