Module kotlinx-coroutines-core

Core primitives to work with coroutines.

Coroutine builder functions:

Name	Result	Scope	Description
launch	Job	CoroutineScope	Launches coroutine that does not have any result
async	Deferred	CoroutineScope	Returns a single value with the future result
produce	ProducerJob	ProducerScope	Produces a stream of elements
actor	ActorJob	ActorScope	Processes a stream of messages
runBlocking	`T`	CoroutineScope	Blocks the thread while the coroutine runs

Coroutine dispatchers implementing CoroutineDispatcher:

Name	Description
CommonPool	Confines coroutine execution to a shared pool of threads
newSingleThreadContext	Create new single-threaded coroutine context
newFixedThreadPoolContext	Creates new thread pool of a fixed size
Executor.asCoroutineDispatcher	Extension to convert any executor
Unconfined	Does not confine coroutine execution in any way

More context elements:

Name	Description
NonCancellable	A non-cancelable job that is always active
CoroutineExceptionHandler	Handler for uncaught exception

Synchronization primitives for coroutines:

Name	Suspending functions	Description
Mutex	lock	Mutual exclusion
Channel	send, receive	Communication channel (aka queue or exchanger)

Top-level suspending functions:

Name	Description
delay	Non-blocking sleep
yield	Yields thread in single-threaded dispatchers
run	Switches to a different context
withTimeout	Set execution time-limit with exception on timeout
withTimeoutOrNull	Set execution time-limit will null result on timeout

Select expression waits for the result of multiple suspending functions simultaneously:

Receiver	Suspending function	Select clause	Non-suspending version
Job	join	onJoin	isCompleted
Deferred	await	onAwait	isCompleted
SendChannel	send	onSend	offer
ReceiveChannel	receive	onReceive	poll
ReceiveChannel	receiveOrNull	onReceiveOrNull	poll
Mutex	lock	onLock	tryLock
none	delay	onTimeout	none

Cancellation support for user-defined suspending functions is available with suspendCancellableCoroutine helper function. NonCancellable job object is provided to suppress cancellation with run(NonCancellable) {...} block of code.

This module provides debugging facilities for coroutines (run JVM with -ea or -Dkotlinx.coroutines.debug options) and newCoroutineContext function to write user-defined coroutine builders that work with these debugging facilities.

Package kotlinx.coroutines.experimental

General-purpose coroutine builders, contexts, and helper functions.

Package kotlinx.coroutines.experimental.sync

Synchronization primitives (mutex).

Package kotlinx.coroutines.experimental.channels

Channels -- non-blocking primitives for communicating a stream of elements between coroutines.

Package kotlinx.coroutines.experimental.selects

Select expression to perform multiple suspending operations simultaneously until one of them succeeds.