| package kotlinx.coroutines.experimental |
| |
| import java.util.concurrent.TimeUnit |
| import kotlin.coroutines.ContinuationInterceptor |
| |
| /** |
| * This dispatcher _feature_ is implemented by [CoroutineDispatcher] implementations that natively support |
| * non-blocking [delay] function. |
| */ |
| public interface Delay { |
| /** |
| * Delays coroutine for a given time without blocking a thread and resumes it after a specified time. |
| * This suspending function is cancellable. |
| * If the [Job] of the current coroutine is completed while this suspending function is suspended, this function |
| * immediately resumes with [CancellationException]. |
| */ |
| suspend fun delay(time: Long, unit: TimeUnit = TimeUnit.MILLISECONDS) { |
| require(time >= 0) { "Delay time $time cannot be negative" } |
| if (time <= 0) return // don't delay |
| return suspendCancellableCoroutine { scheduleResumeAfterDelay(time, unit, it) } |
| } |
| |
| /** |
| * Schedules resume of a specified [continuation] after a specified delay [time]. |
| */ |
| fun scheduleResumeAfterDelay(time: Long, unit: TimeUnit, continuation: CancellableContinuation<Unit>) |
| } |
| |
| /** |
| * Delays coroutine for a given time without blocking a thread and resumes it after a specified time. |
| * This suspending function is cancellable. |
| * If the [Job] of the current coroutine is completed while this suspending function is suspended, this function |
| * immediately resumes with [CancellationException]. |
| * |
| * This function delegates to [Delay] implementation of the context [CoroutineDispatcher] if possible, |
| * otherwise it resumes using a built-in single-threaded scheduled executor service. |
| */ |
| suspend fun delay(time: Long, unit: TimeUnit = TimeUnit.MILLISECONDS) { |
| require(time >= 0) { "Delay time $time cannot be negative" } |
| if (time <= 0) return // don't delay |
| return suspendCancellableCoroutine sc@ { cont: CancellableContinuation<Unit> -> |
| (cont.context[ContinuationInterceptor] as? Delay)?.apply { |
| scheduleResumeAfterDelay(time, unit, cont) |
| return@sc |
| } |
| scheduledExecutor.scheduleResumeAfterDelay(time, unit, cont) |
| } |
| } |