Does Thread.sleep method in kotlin blocks the thread? - multithreading

Question

Just started learning Kotlin and I am trying to make sense of the output of the code snippet below. Per my understanding, the output should be in this order -
Right After Thread.sleep call - from main thread
mainline - from main thread
launched in new thread - from pool-1-thread-1 thread
The first coroutine is created and passed to new thread for execution and suspend for 2 secs.
Second coroutine is launched in main thread. Block the main thread for 0.5 sec and print.
Main thread get unblocked, and third print statement is executed.
Lastly, the first coroutine resume execution after 2 secs delay and prints the statement.
However, the actual result printed is -
launched in new thread - from pool-1-thread-1 thread
mainline - from main thread
Right After Thread.sleep call - from main thread
Greatly appreciate if someone could help me understand the logic behind it
fun main() = runBlocking {
val es = Executors.newSingleThreadExecutor()
withContext (es.asCoroutineDispatcher()) {
delay(2000L)
println("launched in new thread - from ${Thread.currentThread().name} thread")
}
launch {
Thread.sleep(500L)
println("Right After Thread.sleep call - from ${Thread.currentThread().name} thread")
}
println("mainline - from ${Thread.currentThread().name} thread")
es.shutdown()
}

Answer 1

You should read the documentation
Calls the specified suspending block with a given coroutine context, suspends until it completes, and returns the result. ... withContext
Launches a new coroutine without blocking the current thread ...
By default, the coroutine is immediately scheduled for execution. Other start options can be specified via start parameter. ... launch
Default – immediately schedules the coroutine for execution according to its context. ... the coroutine code is dispatched for execution later, while the code that invoked the coroutine builder continues execution. ...CoroutineStart.DEFAULT
It means that
first withContext is executed
next a new coroutine is created and scheduled
then println("mainline - from ${Thread.currentThread().name} thread")
es.shutdown() is executed
and finally the coroutine block is executed