Coroutines are a way to handle multithreading in Kotlin, read more about it from the official docs:
https://kotlinlang.org/docs/coroutines-overview.html
An example of a Coroutine in Kotlin
val runBlocking = runBlocking {
sleep(5)
delay(1_000L)
launch {
delay(1_100L)
note("inside launch")
}
note("outside launch")
}
Introducing the suspend keyword
coroutineScopes need to be in wrapping suspend:
suspend fun coroutineFunction(): String {
return coroutineScope {
launch {
println("test")
}
"we return this string"
}
}
runBlocking { println(coroutineFunction()) }
Making Asynchronous API calls using Coroutines
suspend fun call2Apis() {
val call1 = async {
delay(1_000L)
println("got data from api1 @ ${Instant.now()}")
"some data from api1"
}
val call2 = async P
delay(1_500L)
println("got data from api2 @ ${Instant.now()}")
"some data from api2"
}
println(call1.await() + " ${Instant.now()}")
println(call2.await() + " ${Instant.now()}")
}
runBlocking { call2Apis() }
sleep(2)
Sharing states between Coroutines
Simply return a coroutineScope.
suspend fun call2Apis() {
return coroutineScope {
val call1 = async {
delay(1_000L)
println("got data from api1 @ ${Instant.now()}")
"some data from api1"
}
val call2 = async P
println(call1.isCompleted) // false
println(call1.await()) // pause and wait for call1 to complete..
delay(1_500L)
println("got data from api2 @ ${Instant.now()}")
"some data from api2"
}
println(call1.await() + " ${Instant.now()}")
println(call2.await() + " ${Instant.now()}")
}
}
runBlocking { call2Apis() }
sleep(2)
Run tasks as Global Scope
runBlocking {
GlobalScope.launch {
//
}
}
