| /* |
| * Copyright 2016-2018 JetBrains s.r.o. Use of this source code is governed by the Apache 2.0 license. |
| */ |
| |
| package kotlinx.coroutines.experimental |
| |
| import kotlinx.atomicfu.* |
| import kotlinx.coroutines.experimental.internal.* |
| import kotlinx.coroutines.experimental.intrinsics.* |
| import kotlinx.coroutines.experimental.selects.* |
| import kotlin.coroutines.experimental.* |
| |
| /** |
| * A concrete implementation of [Job]. It is optionally a child to a parent job. |
| * This job is cancelled when the parent is complete, but not vise-versa. |
| * |
| * This is an open class designed for extension by more specific classes that might augment the |
| * state and mare store addition state information for completed jobs, like their result values. |
| * |
| * @param active when `true` the job is created in _active_ state, when `false` in _new_ state. See [Job] for details. |
| * @suppress **This is unstable API and it is subject to change.** |
| */ |
| internal open class JobSupport constructor(active: Boolean) : Job, SelectClause0 { |
| final override val key: CoroutineContext.Key<*> get() = Job |
| |
| /* |
| === Internal states === |
| |
| name state class public state description |
| ------ ------------ ------------ ----------- |
| EMPTY_N EmptyNew : New no listeners |
| EMPTY_A EmptyActive : Active no listeners |
| SINGLE JobNode : Active a single listener |
| SINGLE+ JobNode : Active a single listener + NodeList added as its next |
| LIST_N InactiveNodeList : New a list of listeners (promoted once, does not got back to EmptyNew) |
| LIST_A NodeList : Active a list of listeners (promoted once, does not got back to JobNode/EmptyActive) |
| COMPLETING Finishing : Completing has a list of listeners (promoted once from LIST_*) |
| CANCELLING Finishing : Cancelling -- " -- |
| FINAL_C Cancelled : Cancelled cancelled (final state) |
| FINAL_F CompletedExceptionally : Completed failed for other reason (final state) |
| FINAL_R <any> : Completed produced some result |
| |
| === Transitions === |
| |
| New states Active states Inactive states |
| |
| +---------+ +---------+ } |
| | EMPTY_N | ----> | EMPTY_A | ----+ } Empty states |
| +---------+ +---------+ | } |
| | | | ^ | +----------+ |
| | | | | +--> | FINAL_* | |
| | | V | | +----------+ |
| | | +---------+ | } |
| | | | SINGLE | ----+ } JobNode states |
| | | +---------+ | } |
| | | | | } |
| | | V | } |
| | | +---------+ | } |
| | +-------> | SINGLE+ | ----+ } |
| | +---------+ | } |
| | | | |
| V V | |
| +---------+ +---------+ | } |
| | LIST_N | ----> | LIST_A | ----+ } [Inactive]NodeList states |
| +---------+ +---------+ | } |
| | | | | | |
| | | +--------+ | | |
| | | | V | |
| | | | +------------+ | +------------+ } |
| | +-------> | COMPLETING | --+-- | CANCELLING | } Finishing states |
| | | +------------+ +------------+ } |
| | | | ^ |
| | | | | |
| +--------+---------+--------------------+ |
| |
| |
| This state machine and its transition matrix are optimized for the common case when job is created in active |
| state (EMPTY_A), at most one completion listener is added to it during its life-time, and it completes |
| successfully without children (in this case it directly goes from EMPTY_A or SINGLE state to FINAL_R |
| state without going to COMPLETING state) |
| |
| Note, that the actual `_state` variable can also be a reference to atomic operation descriptor `OpDescriptor` |
| */ |
| |
| // Note: use shared objects while we have no listeners |
| private val _state = atomic<Any?>(if (active) EMPTY_ACTIVE else EMPTY_NEW) |
| |
| @Volatile |
| private var parentHandle: DisposableHandle? = null |
| |
| // ------------ initialization ------------ |
| |
| /** |
| * Initializes parent job. |
| * It shall be invoked at most once after construction after all other initialization. |
| * @suppress **This is unstable API and it is subject to change.** |
| */ |
| internal fun initParentJobInternal(parent: Job?) { |
| check(parentHandle == null) |
| if (parent == null) { |
| parentHandle = NonDisposableHandle |
| return |
| } |
| parent.start() // make sure the parent is started |
| @Suppress("DEPRECATION") |
| val handle = parent.attachChild(this) |
| parentHandle = handle |
| // now check our state _after_ registering (see tryFinalizeSimpleState order of actions) |
| if (isCompleted) { |
| handle.dispose() |
| parentHandle = NonDisposableHandle // release it just in case, to aid GC |
| } |
| } |
| |
| // ------------ state query ------------ |
| |
| /** |
| * Returns current state of this job. |
| * @suppress **This is unstable API and it is subject to change.** |
| */ |
| internal val state: Any? get() { |
| _state.loop { state -> // helper loop on state (complete in-progress atomic operations) |
| if (state !is OpDescriptor) return state |
| state.perform(this) |
| } |
| } |
| |
| /** |
| * @suppress **This is unstable API and it is subject to change.** |
| */ |
| private inline fun loopOnState(block: (Any?) -> Unit): Nothing { |
| while (true) { |
| block(state) |
| } |
| } |
| |
| public override val isActive: Boolean get() { |
| val state = this.state |
| return state is Incomplete && state.isActive |
| } |
| |
| public final override val isCompleted: Boolean get() = state !is Incomplete |
| |
| public final override val isFailed: Boolean get() { |
| val state = this.state |
| return state is CompletedExceptionally || (state is Finishing && state.isFailing) |
| } |
| |
| public final override val isCancelled: Boolean get() { |
| val state = this.state |
| return state is Cancelled || (state is Finishing && state.isCancelling) |
| } |
| |
| // ------------ state update ------------ |
| |
| // Finalizes Finishing -> Completed (terminal state) transition. |
| // ## IMPORTANT INVARIANT: Only one thread can be concurrently invoking this method. |
| private fun tryFinalizeFinishingState(state: Finishing, proposedUpdate: Any?, mode: Int): Boolean { |
| require(proposedUpdate !is Incomplete) // only incomplete -> completed transition is allowed |
| require(this.state === state) // consistency check -- it cannot change |
| require(!state.isSealed) // consistency check -- cannot be sealed yet |
| require(state.isCompleting) // consistency check -- must be marked as completing |
| val proposedException = (proposedUpdate as? CompletedExceptionally)?.cause |
| val proposedCancel = proposedUpdate is Cancelled |
| // Create the final exception and seal the state so that no more exceptions can be added |
| var suppressed = false |
| val finalException = synchronized(state) { |
| val exceptions = state.sealLocked(proposedException) |
| val rootCause = getFinalRootCause(state, exceptions) |
| if (rootCause != null) suppressed = suppressExceptions(rootCause, exceptions) |
| rootCause |
| } |
| // Create the final state object |
| val finalState = when { |
| // if we have not failed -> use proposed update value |
| finalException == null -> proposedUpdate |
| // small optimization when we can used proposeUpdate object as is on failure |
| finalException === proposedException && proposedCancel == state.isCancelling -> proposedUpdate |
| // cancelled job final state |
| state.isCancelling -> Cancelled(finalException) |
| // failed job final state |
| else -> CompletedExceptionally(finalException) |
| } |
| // Now handle exception |
| if (finalException != null) { |
| if (!failParent(finalException)) handleJobException(finalException) |
| } |
| // Then CAS to completed state -> it must succeed |
| require(_state.compareAndSet(state, finalState)) { "Unexpected state: ${_state.value}, expected: $state, update: $finalState" } |
| // And process all post-completion actions |
| completeStateFinalization(state, finalState, mode, suppressed) |
| return true |
| } |
| |
| private fun getFinalRootCause(state: Finishing, exceptions: List<Throwable>): Throwable? { |
| // A case of no exceptions |
| if (exceptions.isEmpty()) { |
| // materialize cancellation exception if it was not materialized yet |
| if (state.isCancelling) return createJobCancellationException() |
| return null |
| } |
| /* |
| * This is a place where we step on our API limitation: |
| * We can't distinguish internal JobCancellationException from our parent |
| * from external cancellation, thus we ought to collect all exceptions. |
| * |
| * But it has negative consequences: same exception can be added as suppressed more than once. |
| * Consider concurrent parent-child relationship: |
| * 1) Child throws E1 and parent throws E2. |
| * 2) Parent goes to "Failing(E1)" and cancels child with E1 |
| * 3) Child goes to "Cancelling(E1)", but throws an exception E2 |
| * 4) When child throws, it notifies parent that it is failing, adding its exception to parent's list of exceptions/ |
| * 5) Child builds final exception: E1 with suppressed E2, reports it to parent. |
| * 6) Parent aggregates three exceptions: original E1, reported E2 and "final" E1. |
| * It filters the third exception, but adds the second one to the first one, thus adding suppressed duplicate. |
| * |
| * Note that it's only happening when both parent and child throw exception simultaneously. |
| */ |
| var rootCause = exceptions[0] |
| if (rootCause is JobCancellationException) { |
| val cause = unwrap(rootCause) |
| rootCause = if (cause !== null) { |
| cause |
| } else { |
| exceptions.firstOrNull { unwrap(it) != null } ?: return rootCause |
| } |
| } |
| return rootCause |
| } |
| |
| private fun suppressExceptions(rootCause: Throwable, exceptions: List<Throwable>): Boolean { |
| if (exceptions.size <= 1) return false // nothing more to do here |
| // TODO it should be identity set and optimized for small footprints |
| val seenExceptions = HashSet<Throwable>(exceptions.size) |
| var suppressed = false |
| for (i in 1 until exceptions.size) { |
| val unwrapped = unwrap(exceptions[i]) |
| if (unwrapped !== null && unwrapped !== rootCause) { |
| if (seenExceptions.add(unwrapped)) { |
| rootCause.addSuppressedThrowable(unwrapped) |
| suppressed = true |
| } |
| } |
| } |
| return suppressed |
| } |
| |
| private tailrec fun unwrap(exception: Throwable): Throwable? = |
| if (exception is JobCancellationException) { |
| val cause = exception.cause |
| if (cause !== null) unwrap(cause) else null |
| } else { |
| exception |
| } |
| |
| // fast-path method to finalize normally completed coroutines without children |
| private fun tryFinalizeSimpleState(state: Incomplete, update: Any?, mode: Int): Boolean { |
| check(state is Empty || state is JobNode<*>) // only simple state without lists where children can concurrently add |
| check(update !is CompletedExceptionally) // only for normal completion |
| if (!_state.compareAndSet(state, update)) return false |
| completeStateFinalization(state, update, mode, false) |
| return true |
| } |
| |
| // suppressed == true when any exceptions were suppressed while building the final completion cause |
| private fun completeStateFinalization(state: Incomplete, update: Any?, mode: Int, suppressed: Boolean) { |
| /* |
| * Now the job in THE FINAL state. We need to properly handle the resulting state. |
| * Order of various invocations here is important. |
| * |
| * 1) Unregister from parent job. |
| */ |
| parentHandle?.let { |
| it.dispose() // volatile read parentHandle _after_ state was updated |
| parentHandle = NonDisposableHandle // release it just in case, to aid GC |
| } |
| val cause = (update as? CompletedExceptionally)?.cause |
| /* |
| * 2) Invoke onFailing: for resource cancellation resource cancellation etc. |
| * Only notify is was not notified yet. |
| * Note: we do not use notifyFailing here, since we are going to invoke all completion as our next step |
| */ |
| if (!state.isFailing) onFailing(cause) |
| /* |
| * 3) Invoke completion handlers: .join(), callbacks etc. |
| * It's important to invoke them only AFTER exception handling, see #208 |
| */ |
| if (state is JobNode<*>) { // SINGLE/SINGLE+ state -- one completion handler (common case) |
| try { |
| state.invoke(cause) |
| } catch (ex: Throwable) { |
| handleOnCompletionException(CompletionHandlerException("Exception in completion handler $state for $this", ex)) |
| } |
| } else { |
| state.list?.notifyCompletion(cause) |
| } |
| /* |
| * 4) Invoke onCompletionInternal: onNext(), timeout de-registration etc. |
| * It should be last so all callbacks observe consistent state |
| * of the job which doesn't depend on callback scheduling. |
| */ |
| onCompletionInternal(update, mode, suppressed) |
| } |
| |
| private fun notifyFailing(list: NodeList, cause: Throwable) { |
| // first cancel our own children |
| onFailing(cause) |
| notifyHandlers<JobFailingNode<*>>(list, cause) |
| // then report to the parent that we are failing |
| failParent(cause) // tentative failure report -- does not matter if there is no parent |
| } |
| |
| private fun NodeList.notifyCompletion(cause: Throwable?) = |
| notifyHandlers<JobNode<*>>(this, cause) |
| |
| private inline fun <reified T: JobNode<*>> notifyHandlers(list: NodeList, cause: Throwable?) { |
| var exception: Throwable? = null |
| list.forEach<T> { node -> |
| try { |
| node.invoke(cause) |
| } catch (ex: Throwable) { |
| exception?.apply { addSuppressedThrowable(ex) } ?: run { |
| exception = CompletionHandlerException("Exception in completion handler $node for $this", ex) |
| } |
| } |
| } |
| exception?.let { handleOnCompletionException(it) } |
| } |
| |
| public final override fun start(): Boolean { |
| loopOnState { state -> |
| when (startInternal(state)) { |
| FALSE -> return false |
| TRUE -> return true |
| } |
| } |
| } |
| |
| // returns: RETRY/FALSE/TRUE: |
| // FALSE when not new, |
| // TRUE when started |
| // RETRY when need to retry |
| private fun startInternal(state: Any?): Int { |
| when (state) { |
| is Empty -> { // EMPTY_X state -- no completion handlers |
| if (state.isActive) return FALSE // already active |
| if (!_state.compareAndSet(state, EMPTY_ACTIVE)) return RETRY |
| onStartInternal() |
| return TRUE |
| } |
| is InactiveNodeList -> { // LIST state -- inactive with a list of completion handlers |
| if (!_state.compareAndSet(state, state.list)) return RETRY |
| onStartInternal() |
| return TRUE |
| } |
| else -> return FALSE // not a new state |
| } |
| } |
| |
| /** |
| * Override to provide the actual [start] action. |
| * This function is invoked exactly once when non-active coroutine is [started][start]. |
| */ |
| internal open fun onStartInternal() {} |
| |
| public final override fun getCancellationException(): CancellationException { |
| val state = this.state |
| return when (state) { |
| is Finishing -> state.rootCause?.toCancellationException("Job is failing") |
| ?: error("Job is still new or active: $this") |
| is Incomplete -> error("Job is still new or active: $this") |
| is CompletedExceptionally -> state.cause.toCancellationException("Job has failed") |
| else -> JobCancellationException("Job has completed normally", null, this) |
| } |
| } |
| |
| private fun Throwable.toCancellationException(message: String): CancellationException = |
| this as? CancellationException ?: JobCancellationException(message, this, this@JobSupport) |
| |
| /** |
| * Returns the cause that signals the completion of this job -- it returns the original |
| * [cancel] cause, [JobCancellationException] or **`null` if this job had completed normally**. |
| * This function throws [IllegalStateException] when invoked for an job that has not [completed][isCompleted] nor |
| * failing yet. |
| * |
| * @suppress **This is unstable API and it is subject to change.** |
| */ |
| protected fun getCompletionCause(): Throwable? = loopOnState { state -> |
| return when (state) { |
| is Finishing -> state.rootCause |
| ?: error("Job is still new or active: $this") |
| is Incomplete -> error("Job is still new or active: $this") |
| is CompletedExceptionally -> state.cause |
| else -> null |
| } |
| } |
| |
| @Suppress("OverridingDeprecatedMember") |
| public final override fun invokeOnCompletion(handler: CompletionHandler): DisposableHandle = |
| invokeOnCompletion(onFailing = false, invokeImmediately = true, handler = handler) |
| |
| @Suppress("OverridingDeprecatedMember") |
| public final override fun invokeOnCompletion(handler: CompletionHandler, onCancelling: Boolean): DisposableHandle = |
| invokeOnCompletion(onFailing = onCancelling, invokeImmediately = true, handler = handler) |
| |
| @Suppress("OverridingDeprecatedMember") |
| public final override fun invokeOnCompletion(onCancelling_: Boolean, handler: CompletionHandler): DisposableHandle = |
| invokeOnCompletion(onFailing = onCancelling_, invokeImmediately = true, handler = handler) |
| |
| // todo: non-final as a workaround for KT-21968, should be final in the future |
| public override fun invokeOnCompletion( |
| onFailing: Boolean, |
| invokeImmediately: Boolean, |
| handler: CompletionHandler |
| ): DisposableHandle { |
| var nodeCache: JobNode<*>? = null |
| loopOnState { state -> |
| when (state) { |
| is Empty -> { // EMPTY_X state -- no completion handlers |
| if (state.isActive) { |
| // try move to SINGLE state |
| val node = nodeCache ?: makeNode(handler, onFailing).also { nodeCache = it } |
| if (_state.compareAndSet(state, node)) return node |
| } else |
| promoteEmptyToNodeList(state) // that way we can add listener for non-active coroutine |
| } |
| is Incomplete -> { |
| val list = state.list |
| if (list == null) { // SINGLE/SINGLE+ |
| promoteSingleToNodeList(state as JobNode<*>) |
| } else { |
| var rootCause: Throwable? = null |
| var handle: DisposableHandle = NonDisposableHandle |
| if (onFailing && state is Finishing) { |
| synchronized(state) { |
| // check if we are installing failing handler on job that is failing |
| rootCause = state.rootCause // != null if we are failing |
| // We add node to the list in two cases --- either the job is not failing |
| // or we are adding a child to a coroutine that is not completing yet |
| if (rootCause == null || handler.isHandlerOf<ChildJob>() && !state.isCompleting) { |
| // Note: add node the list while holding lock on state (make sure it cannot change) |
| val node = nodeCache ?: makeNode(handler, onFailing).also { nodeCache = it } |
| if (!addLastAtomic(state, list, node)) return@loopOnState // retry |
| // just return node if we don't have to invoke handler (not failing yet) |
| if (rootCause == null) return node |
| // otherwise handler is invoked immediately out of the synchronized section & handle returned |
| handle = node |
| } |
| } |
| } |
| if (rootCause != null) { |
| // Note: attachChild uses invokeImmediately, so it gets invoked when adding to failing job |
| if (invokeImmediately) handler.invokeIt(rootCause) |
| return handle |
| } else { |
| val node = nodeCache ?: makeNode(handler, onFailing).also { nodeCache = it } |
| if (addLastAtomic(state, list, node)) return node |
| } |
| } |
| } |
| else -> { // is complete |
| // :KLUDGE: We have to invoke a handler in platform-specific way via `invokeIt` extension, |
| // because we play type tricks on Kotlin/JS and handler is not necessarily a function there |
| if (invokeImmediately) handler.invokeIt((state as? CompletedExceptionally)?.cause) |
| return NonDisposableHandle |
| } |
| } |
| } |
| } |
| |
| private fun makeNode(handler: CompletionHandler, onCancelling: Boolean): JobNode<*> { |
| return if (onCancelling) |
| (handler as? JobFailingNode<*>)?.also { require(it.job === this) } |
| ?: InvokeOnFailing(this, handler) |
| else |
| (handler as? JobNode<*>)?.also { require(it.job === this && it !is JobFailingNode) } |
| ?: InvokeOnCompletion(this, handler) |
| } |
| |
| private fun addLastAtomic(expect: Any, list: NodeList, node: JobNode<*>) = |
| list.addLastIf(node) { this.state === expect } |
| |
| private fun promoteEmptyToNodeList(state: Empty) { |
| // try to promote it to LIST state with the corresponding state |
| val list = NodeList() |
| val update = if (state.isActive) list else InactiveNodeList(list) |
| _state.compareAndSet(state, update) |
| } |
| |
| private fun promoteSingleToNodeList(state: JobNode<*>) { |
| // try to promote it to list (SINGLE+ state) |
| state.addOneIfEmpty(NodeList()) |
| // it must be in SINGLE+ state or state has changed (node could have need removed from state) |
| val list = state.nextNode // either our NodeList or somebody else won the race, updated state |
| // just attempt converting it to list if state is still the same, then we'll continue lock-free loop |
| _state.compareAndSet(state, list) |
| } |
| |
| public final override suspend fun join() { |
| if (!joinInternal()) { // fast-path no wait |
| coroutineContext.checkCompletion() |
| return // do not suspend |
| } |
| return joinSuspend() // slow-path wait |
| } |
| |
| private fun joinInternal(): Boolean { |
| loopOnState { state -> |
| if (state !is Incomplete) return false // not active anymore (complete) -- no need to wait |
| if (startInternal(state) >= 0) return true // wait unless need to retry |
| } |
| } |
| |
| private suspend fun joinSuspend() = suspendCancellableCoroutine<Unit> { cont -> |
| // We have to invoke join() handler only on cancellation, on completion we will be resumed regularly without handlers |
| cont.disposeOnCancellation(invokeOnCompletion(handler = ResumeOnCompletion(this, cont).asHandler)) |
| } |
| |
| public final override val onJoin: SelectClause0 |
| get() = this |
| |
| // registerSelectJoin |
| public final override fun <R> registerSelectClause0(select: SelectInstance<R>, block: suspend () -> R) { |
| // fast-path -- check state and select/return if needed |
| loopOnState { state -> |
| if (select.isSelected) return |
| if (state !is Incomplete) { |
| // already complete -- select result |
| if (select.trySelect(null)) { |
| select.completion.context.checkCompletion() // always check for our completion |
| block.startCoroutineUnintercepted(select.completion) |
| } |
| return |
| } |
| if (startInternal(state) == 0) { |
| // slow-path -- register waiter for completion |
| select.disposeOnSelect(invokeOnCompletion(handler = SelectJoinOnCompletion(this, select, block).asHandler)) |
| return |
| } |
| } |
| } |
| |
| /** |
| * @suppress **This is unstable API and it is subject to change.** |
| */ |
| internal fun removeNode(node: JobNode<*>) { |
| // remove logic depends on the state of the job |
| loopOnState { state -> |
| when (state) { |
| is JobNode<*> -> { // SINGE/SINGLE+ state -- one completion handler |
| if (state !== node) return // a different job node --> we were already removed |
| // try remove and revert back to empty state |
| if (_state.compareAndSet(state, EMPTY_ACTIVE)) return |
| } |
| is Incomplete -> { // may have a list of completion handlers |
| // remove node from the list if there is a list |
| if (state.list != null) node.remove() |
| return |
| } |
| else -> return // it is complete and does not have any completion handlers |
| } |
| } |
| } |
| |
| /** |
| * Returns `true` for job that do not have "body block" to complete and should immediately go into |
| * completing state and start waiting for children. |
| * |
| * @suppress **This is unstable API and it is subject to change.** |
| */ |
| internal open val onFailComplete: Boolean get() = false |
| |
| // external cancel with (optional) cause |
| public override fun cancel(cause: Throwable?): Boolean = |
| fail(cause, cancel = true) && handlesException |
| |
| // child is reporting failure to the parent |
| public override fun childFailed(cause: Throwable) = |
| fail(cause, cancel = false) && handlesException |
| |
| // parent is cancelling child |
| public override fun cancelChild(parentJob: Job) { |
| fail(parentJob, cancel = true) |
| } |
| |
| // cause is Throwable or Job when cancelChild was invoked, cause can be null only on cancel |
| // returns true is exception was handled, false otherwise |
| private fun fail(cause: Any?, cancel: Boolean): Boolean { |
| if (onFailComplete) { |
| // make sure it is completing, if failMakeCompleting returns true it means it had make it |
| // completing and had recorded exception |
| if (failMakeCompleting(cause, cancel)) return true |
| // otherwise just record failure via makeFailing below |
| } |
| return makeFailing(cause, cancel) |
| } |
| |
| private fun failMakeCompleting(cause: Any?, cancel: Boolean): Boolean { |
| loopOnState { state -> |
| if (state !is Incomplete || state is Finishing && state.isCompleting) { |
| return false // already completed/completing, do not even propose update |
| } |
| val proposedUpdate = createFailure(createCauseException(cause), cancel) |
| when (tryMakeCompleting(state, proposedUpdate, mode = MODE_ATOMIC_DEFAULT)) { |
| COMPLETING_ALREADY_COMPLETING -> return false |
| COMPLETING_COMPLETED, COMPLETING_WAITING_CHILDREN -> return true |
| COMPLETING_RETRY -> return@loopOnState |
| else -> error("unexpected result") |
| } |
| } |
| } |
| |
| private fun createJobCancellationException() = |
| JobCancellationException("Job was cancelled", null, this) |
| |
| // cause is Throwable or Job when cancelChild was invoked, cause can be null only on cancel |
| private fun createCauseException(cause: Any?): Throwable = when(cause) { |
| is Throwable? -> cause ?: createJobCancellationException() |
| else -> (cause as Job).getCancellationException() |
| } |
| |
| private fun createFailure(causeException: Throwable, cancel: Boolean): CompletedExceptionally = |
| when { |
| cancel -> Cancelled(causeException) |
| else -> CompletedExceptionally(causeException) |
| } |
| |
| // transitions to Failing state |
| // cause is Throwable or Job when cancelChild was invoked, cause can be null only on cancel |
| private fun makeFailing(cause: Any?, cancel: Boolean): Boolean { |
| var causeExceptionCache: Throwable? = null // lazily init result of createCauseException(cause) |
| loopOnState { state -> |
| when (state) { |
| is Finishing -> { // already finishing -- collect exceptions |
| var notifyRootCause: Throwable? = null |
| synchronized(state) { |
| if (state.isSealed) return false // too late, already sealed -- cannot add exception nor mark cancelled |
| // add exception, do nothing is parent is cancelling child that is already failing |
| val wasFailing = state.isFailing // will notify if was not failing |
| // Materialize missing exception if it is the first exception (otherwise -- don't) |
| if (cause != null || !wasFailing) { |
| val causeException = causeExceptionCache ?: createCauseException(cause).also { causeExceptionCache = it } |
| state.addExceptionLocked(causeException) |
| } |
| // mark as cancelling if cancel was requested |
| if (cancel) state.isCancelling = true |
| // take cause for notification is was not failing before |
| notifyRootCause = state.rootCause.takeIf { !wasFailing } |
| } |
| notifyRootCause?.let { notifyFailing(state.list, it) } |
| return true |
| } |
| is Incomplete -> { |
| // Not yet finishing -- try to make it failing |
| val list = tryPromoteToList(state) ?: return@loopOnState |
| val causeException = causeExceptionCache ?: createCauseException(cause).also { causeExceptionCache = it } |
| if (state.isActive) { |
| // active state becomes failing |
| if (tryMakeFailing(state, list, causeException, cancel)) return true |
| } else { |
| // non active state starts completing |
| when (tryMakeCompleting(state, createFailure(causeException, cancel), mode = MODE_ATOMIC_DEFAULT)) { |
| COMPLETING_ALREADY_COMPLETING -> error("Cannot happen in $state") |
| COMPLETING_COMPLETED, COMPLETING_WAITING_CHILDREN -> return true // ok |
| COMPLETING_RETRY -> return@loopOnState |
| else -> error("unexpected result") |
| } |
| } |
| } |
| else -> return false // already complete |
| } |
| } |
| } |
| |
| // Performs promotion of incomplete coroutine state to NodeList, returns null when need to retry |
| private fun tryPromoteToList(state: Incomplete): NodeList? = state.list ?: null.also { |
| when (state) { |
| is Empty -> promoteEmptyToNodeList(state) |
| is JobNode<*> -> promoteSingleToNodeList(state) |
| else -> error("State should have list: $state") |
| } |
| } |
| |
| // try make new failing state on the condition that we're still in the expected state |
| private fun tryMakeFailing(state: Incomplete, list: NodeList, rootCause: Throwable, cancel: Boolean): Boolean { |
| check(state !is Finishing) // only for non-finishing states |
| check(state.isActive) // only for active states |
| // Create failing state (with rootCause!) |
| val failing = Finishing(list, cancel, false, rootCause) |
| if (!_state.compareAndSet(state, failing)) return false |
| // Notify listeners |
| notifyFailing(list, rootCause) |
| return true |
| } |
| |
| /** |
| * This function is used by [CompletableDeferred.complete] (and exceptionally) and by [JobImpl.cancel]. |
| * It returns `false` on repeated invocation (when this job is already completing). |
| * |
| * @suppress **This is unstable API and it is subject to change.** |
| */ |
| internal fun makeCompleting(proposedUpdate: Any?): Boolean = loopOnState { state -> |
| when (tryMakeCompleting(state, proposedUpdate, mode = MODE_ATOMIC_DEFAULT)) { |
| COMPLETING_ALREADY_COMPLETING -> return false |
| COMPLETING_COMPLETED, COMPLETING_WAITING_CHILDREN -> return true |
| COMPLETING_RETRY -> return@loopOnState |
| else -> error("unexpected result") |
| } |
| } |
| |
| /** |
| * This function is used by [AbstractCoroutine.resume]. |
| * It throws exception on repeated invocation (when this job is already completing). |
| * |
| * Returns: |
| * * `true` if state was updated to completed/cancelled; |
| * * `false` if made completing or it is cancelling and is waiting for children. |
| * |
| * @throws IllegalStateException if job is already complete or completing |
| * @suppress **This is unstable API and it is subject to change.** |
| */ |
| internal fun makeCompletingOnce(proposedUpdate: Any?, mode: Int): Boolean = loopOnState { state -> |
| when (tryMakeCompleting(state, proposedUpdate, mode)) { |
| COMPLETING_ALREADY_COMPLETING -> throw IllegalStateException("Job $this is already complete or completing, " + |
| "but is being completed with $proposedUpdate", proposedUpdate.exceptionOrNull) |
| COMPLETING_COMPLETED -> return true |
| COMPLETING_WAITING_CHILDREN -> return false |
| COMPLETING_RETRY -> return@loopOnState |
| else -> error("unexpected result") |
| } |
| } |
| |
| private fun tryMakeCompleting(state: Any?, proposedUpdate: Any?, mode: Int): Int { |
| if (state !is Incomplete) |
| return COMPLETING_ALREADY_COMPLETING |
| // find first child |
| val child = firstChild(state) |
| // FAST PATH -- no children to wait for && simple state (no list) && not failing => can complete immediately |
| // Failures always have to go through Finishing state to serialize exception handling |
| if (child == null && (state is Empty || state is JobNode<*>) && proposedUpdate !is CompletedExceptionally) { |
| if (!tryFinalizeSimpleState(state, proposedUpdate, mode)) return COMPLETING_RETRY |
| return COMPLETING_COMPLETED |
| } |
| // get state's list or else promote to list to correctly operate on child lists |
| val list = tryPromoteToList(state) ?: return COMPLETING_RETRY |
| // promote to Finishing state if we are not in it yet |
| // This promotion has to be atomic w.r.t to state change, so that a coroutine that is not active yet |
| // atomically transition to finishing & completing state |
| val finishing = state as? Finishing ?: Finishing(list, false, false, null) |
| // must synchronize updates to finishing state |
| var notifyRootCause: Throwable? = null |
| synchronized(finishing) { |
| // check if this state is already completing |
| if (finishing.isCompleting) return COMPLETING_ALREADY_COMPLETING |
| // mark as completing |
| finishing.isCompleting = true |
| // ## IMPORTANT INVARIANT: Only one thread (that had set isCompleting) can go past this point |
| require(!finishing.isSealed) // cannot be sealed |
| // mark as cancelling is the proposed update is to cancel |
| if (proposedUpdate is Cancelled) finishing.isCancelling = true |
| // add new proposed exception to the finishing state |
| val wasFailing = finishing.isFailing |
| (proposedUpdate as? CompletedExceptionally)?.let { finishing.addExceptionLocked(it.cause) } |
| // If it just becomes failing --> must process failing notifications |
| notifyRootCause = finishing.rootCause.takeIf { !wasFailing } |
| } |
| // if we need to promote to finishing then atomically do it here |
| if (finishing !== state) { |
| if (!_state.compareAndSet(state, finishing)) return COMPLETING_RETRY |
| } |
| // process failing notification here -- it cancels all the children _before_ we start to to wait them (sic!!!) |
| notifyRootCause?.let { notifyFailing(list, it) } |
| // now wait for children |
| if (child != null && tryWaitForChild(finishing, child, proposedUpdate)) |
| return COMPLETING_WAITING_CHILDREN |
| // otherwise -- we have not children left (all were already cancelled?) |
| if (tryFinalizeFinishingState(finishing, proposedUpdate, mode)) |
| return COMPLETING_COMPLETED |
| // otherwise retry |
| return COMPLETING_RETRY |
| } |
| |
| private val Any?.exceptionOrNull: Throwable? |
| get() = (this as? CompletedExceptionally)?.cause |
| |
| private fun firstChild(state: Incomplete) = |
| state as? ChildJob ?: state.list?.nextChild() |
| |
| // return false when there is no more incomplete children to wait |
| // ## IMPORTANT INVARIANT: Only one thread can be concurrently invoking this method. |
| private tailrec fun tryWaitForChild(state: Finishing, child: ChildJob, proposedUpdate: Any?): Boolean { |
| val handle = child.childJob.invokeOnCompletion( |
| invokeImmediately = false, |
| handler = ChildCompletion(this, state, child, proposedUpdate).asHandler |
| ) |
| if (handle !== NonDisposableHandle) return true // child is not complete and we've started waiting for it |
| val nextChild = child.nextChild() ?: return false |
| return tryWaitForChild(state, nextChild, proposedUpdate) |
| } |
| |
| // ## IMPORTANT INVARIANT: Only one thread can be concurrently invoking this method. |
| private fun continueCompleting(state: Finishing, lastChild: ChildJob, proposedUpdate: Any?) { |
| require(this.state === state) // consistency check -- it cannot change while we are waiting for children |
| // figure out if we need to wait for next child |
| val waitChild = lastChild.nextChild() |
| // try wait for next child |
| if (waitChild != null && tryWaitForChild(state, waitChild, proposedUpdate)) return // waiting for next child |
| // no more children to wait -- try update state |
| if (tryFinalizeFinishingState(state, proposedUpdate, MODE_ATOMIC_DEFAULT)) return |
| } |
| |
| private fun LockFreeLinkedListNode.nextChild(): ChildJob? { |
| var cur = this |
| while (cur.isRemoved) cur = cur.prevNode // rollback to prev non-removed (or list head) |
| while (true) { |
| cur = cur.nextNode |
| if (cur.isRemoved) continue |
| if (cur is ChildJob) return cur |
| if (cur is NodeList) return null // checked all -- no more children |
| } |
| } |
| |
| public final override val children: Sequence<Job> get() = buildSequence { |
| val state = this@JobSupport.state |
| when (state) { |
| is ChildJob -> yield(state.childJob) |
| is Incomplete -> state.list?.let { list -> |
| list.forEach<ChildJob> { yield(it.childJob) } |
| } |
| } |
| } |
| |
| @Suppress("OverridingDeprecatedMember") |
| public final override fun attachChild(child: Job): DisposableHandle { |
| /* |
| * Note: This function attaches a special ChildNode object. This node object |
| * is handled in a special way on completion on the coroutine (we wait for all of them) and |
| * is handled specially by invokeOnCompletion itself -- it adds this node to the list even |
| * if the job is already failing. |
| */ |
| return invokeOnCompletion(onFailing = true, handler = ChildJob(this, child).asHandler) |
| } |
| |
| @Suppress("OverridingDeprecatedMember") |
| public final override fun cancelChildren(cause: Throwable?) { |
| this.cancelChildren(cause) // use extension function |
| } |
| |
| /** |
| * Override to process any exceptions that were encountered while invoking completion handlers |
| * installed via [invokeOnCompletion]. |
| * @suppress **This is unstable API and it is subject to change.** |
| */ |
| internal open fun handleOnCompletionException(exception: Throwable) { |
| throw exception |
| } |
| |
| /** |
| * This function is invoked once when job is failing or is completed. |
| * It's an optimization for [invokeOnCompletion] with `onCancelling` set to `true`. |
| * |
| * @suppress **This is unstable API and it is subject to change.* |
| */ |
| internal open fun onFailing(cause: Throwable?) {} |
| |
| // todo: make it for all kinds of coroutines, now only launch & actor override and handleExceptionViaJob |
| internal open fun failParent(exception: Throwable): Boolean = false |
| |
| /** |
| * Returns `true` for jobs that handle their exceptions via [handleJobException] or integrate them |
| * into the job's result via [onCompletionInternal]. The only instance of the [Job] that does not |
| * handle its exceptions is [JobImpl]. |
| * |
| * @suppress **This is unstable API and it is subject to change.* |
| */ |
| protected open val handlesException: Boolean get() = true |
| |
| /** |
| * This method is invoked **exactly once** when the final exception of the job is determined |
| * and before it becomes complete. At the moment of invocation the job and all its children are complete. |
| * |
| * @suppress **This is unstable API and it is subject to change.* |
| */ |
| protected open fun handleJobException(exception: Throwable) {} |
| |
| /** |
| * Override for post-completion actions that need to do something with the state. |
| * @param state the final state. |
| * @param mode completion mode. |
| * @param suppressed true when any exceptions were suppressed while building the final completion cause. |
| * @suppress **This is unstable API and it is subject to change.** |
| */ |
| internal open fun onCompletionInternal(state: Any?, mode: Int, suppressed: Boolean) {} |
| |
| // for nicer debugging |
| public override fun toString(): String = |
| "${nameString()}{${stateString()}}@$hexAddress" |
| |
| /** |
| * @suppress **This is unstable API and it is subject to change.** |
| */ |
| internal open fun nameString(): String = classSimpleName |
| |
| private fun stateString(): String { |
| val state = this.state |
| return when (state) { |
| is Finishing -> buildString { |
| when { // cancelling implies failing |
| state.isCancelling -> append("Cancelling") |
| state.isFailing -> append("Failing") |
| else -> append("Active") |
| } |
| if (state.isCompleting) append("Completing") |
| } |
| is Incomplete -> if (state.isActive) "Active" else "New" |
| is Cancelled -> "Cancelled" |
| is CompletedExceptionally -> "Failed" |
| else -> "Completed" |
| } |
| } |
| |
| // Completing, Failing, Cancelling states, |
| // All updates are guarded by synchronized(this), reads are volatile |
| @Suppress("UNCHECKED_CAST") |
| private class Finishing( |
| override val list: NodeList, |
| @Volatile |
| @JvmField var isCancelling: Boolean, |
| @Volatile |
| @JvmField var isCompleting: Boolean, |
| @Volatile |
| @JvmField var rootCause: Throwable? // NOTE: rootCause is kept even when SEALED |
| ) : SynchronizedObject(), Incomplete { |
| @Volatile |
| private var _exceptionsHolder: Any? = null // Contains null | Throwable | ArrayList | SEALED |
| |
| // NotE: cannot be modified when sealed |
| val isSealed: Boolean get() = _exceptionsHolder === SEALED |
| val isFailing: Boolean get() = rootCause != null |
| override val isActive: Boolean get() = !isFailing |
| |
| // Seals current state and returns list of exceptions |
| // guarded by `synchronized(this)` |
| fun sealLocked(proposedException: Throwable?): List<Throwable> { |
| val eh = _exceptionsHolder // volatile read |
| val list = when(eh) { |
| null -> allocateList() |
| is Throwable -> allocateList().also { it.add(eh) } |
| is ArrayList<*> -> eh as ArrayList<Throwable> |
| else -> error("State is $eh") // already sealed -- cannot happen |
| } |
| val rootCause = this.rootCause // volatile read |
| rootCause?.let { list.add(0, it) } // note -- rootCause goes to the beginning |
| if (proposedException != null && proposedException != rootCause) list.add(proposedException) |
| _exceptionsHolder = SEALED |
| return list |
| } |
| |
| // guarded by `synchronized(this)` |
| fun addExceptionLocked(exception: Throwable) { |
| val rootCause = this.rootCause // volatile read |
| if (rootCause == null) { |
| this.rootCause = exception |
| return |
| } |
| if (exception === rootCause) return // nothing to do |
| val eh = _exceptionsHolder // volatile read |
| when (eh) { |
| null -> _exceptionsHolder = exception |
| is Throwable -> { |
| if (exception === eh) return // nothing to do |
| _exceptionsHolder = allocateList().apply { |
| add(eh) |
| add(exception) |
| |
| } |
| } |
| is ArrayList<*> -> (eh as ArrayList<Throwable>).add(exception) |
| else -> error("State is $eh") // already sealed -- cannot happen |
| } |
| } |
| |
| private fun allocateList() = ArrayList<Throwable>(4) |
| |
| override fun toString(): String = |
| "Finishing[cancelling=$isCancelling, completing=$isCompleting, rootCause=$rootCause, exceptions=$_exceptionsHolder, list=$list]" |
| } |
| |
| private val Incomplete.isFailing: Boolean |
| get() = this is Finishing && isFailing |
| |
| private val Incomplete.isCancelling: Boolean |
| get() = this is Finishing && isCancelling |
| |
| // Used by parent that is waiting for child completion |
| private class ChildCompletion( |
| private val parent: JobSupport, |
| private val state: Finishing, |
| private val child: ChildJob, |
| private val proposedUpdate: Any? |
| ) : JobNode<Job>(child.childJob) { |
| override fun invoke(cause: Throwable?) { |
| parent.continueCompleting(state, child, proposedUpdate) |
| } |
| override fun toString(): String = |
| "ChildCompletion[$child, $proposedUpdate]" |
| } |
| |
| /* |
| * ================================================================================================= |
| * This is ready-to-use implementation for Deferred interface. |
| * However, it is not type-safe. Conceptually it just exposes the value of the underlying |
| * completed state as `Any?` |
| * ================================================================================================= |
| */ |
| |
| public val isCompletedExceptionally: Boolean get() = state is CompletedExceptionally |
| |
| public fun getCompletionExceptionOrNull(): Throwable? { |
| val state = this.state |
| check(state !is Incomplete) { "This job has not completed yet" } |
| return state.exceptionOrNull |
| } |
| |
| /** |
| * @suppress **This is unstable API and it is subject to change.** |
| */ |
| internal fun getCompletedInternal(): Any? { |
| val state = this.state |
| check(state !is Incomplete) { "This job has not completed yet" } |
| if (state is CompletedExceptionally) throw state.cause |
| return state |
| } |
| |
| /** |
| * @suppress **This is unstable API and it is subject to change.** |
| */ |
| internal suspend fun awaitInternal(): Any? { |
| // fast-path -- check state (avoid extra object creation) |
| while(true) { // lock-free loop on state |
| val state = this.state |
| if (state !is Incomplete) { |
| // already complete -- just return result |
| if (state is CompletedExceptionally) throw state.cause |
| return state |
| |
| } |
| if (startInternal(state) >= 0) break // break unless needs to retry |
| } |
| return awaitSuspend() // slow-path |
| } |
| |
| private suspend fun awaitSuspend(): Any? = suspendCancellableCoroutine { cont -> |
| // We have to invoke await() handler only on cancellation, on completion we will be resumed regularly without handlers |
| cont.disposeOnCancellation(invokeOnCompletion { |
| val state = this.state |
| check(state !is Incomplete) |
| if (state is CompletedExceptionally) |
| cont.resumeWithException(state.cause) |
| else |
| cont.resume(state) |
| }) |
| } |
| |
| /** |
| * @suppress **This is unstable API and it is subject to change.** |
| */ |
| // registerSelectAwaitInternal |
| @Suppress("UNCHECKED_CAST") |
| internal fun <T, R> registerSelectClause1Internal(select: SelectInstance<R>, block: suspend (T) -> R) { |
| // fast-path -- check state and select/return if needed |
| loopOnState { state -> |
| if (select.isSelected) return |
| if (state !is Incomplete) { |
| // already complete -- select result |
| if (select.trySelect(null)) { |
| if (state is CompletedExceptionally) |
| select.resumeSelectCancellableWithException(state.cause) |
| else |
| block.startCoroutineUnintercepted(state as T, select.completion) |
| } |
| return |
| } |
| if (startInternal(state) == 0) { |
| // slow-path -- register waiter for completion |
| select.disposeOnSelect(invokeOnCompletion(handler = SelectAwaitOnCompletion(this, select, block).asHandler)) |
| return |
| } |
| } |
| } |
| |
| /** |
| * @suppress **This is unstable API and it is subject to change.** |
| */ |
| @Suppress("UNCHECKED_CAST") |
| internal fun <T, R> selectAwaitCompletion(select: SelectInstance<R>, block: suspend (T) -> R) { |
| val state = this.state |
| // Note: await is non-atomic (can be cancelled while dispatched) |
| if (state is CompletedExceptionally) |
| select.resumeSelectCancellableWithException(state.cause) |
| else |
| block.startCoroutineCancellable(state as T, select.completion) |
| } |
| } |
| |
| // --------------- helper classes & constants for job implementation |
| |
| private const val COMPLETING_ALREADY_COMPLETING = 0 |
| private const val COMPLETING_COMPLETED = 1 |
| private const val COMPLETING_WAITING_CHILDREN = 2 |
| private const val COMPLETING_RETRY = 3 |
| |
| private const val RETRY = -1 |
| private const val FALSE = 0 |
| private const val TRUE = 1 |
| |
| private val SEALED = Symbol("SEALED") |
| |
| private val EMPTY_NEW = Empty(false) |
| private val EMPTY_ACTIVE = Empty(true) |
| |
| private class Empty(override val isActive: Boolean) : Incomplete { |
| override val list: NodeList? get() = null |
| override fun toString(): String = "Empty{${if (isActive) "Active" else "New" }}" |
| } |
| |
| internal class JobImpl(parent: Job? = null) : JobSupport(true) { |
| init { initParentJobInternal(parent) } |
| override val onFailComplete get() = true |
| override val handlesException: Boolean get() = false |
| } |
| |
| // -------- invokeOnCompletion nodes |
| |
| internal interface Incomplete { |
| val isActive: Boolean |
| val list: NodeList? // is null only for Empty and JobNode incomplete state objects |
| } |
| |
| internal abstract class JobNode<out J : Job>( |
| @JvmField val job: J |
| ) : CompletionHandlerBase(), DisposableHandle, Incomplete { |
| override val isActive: Boolean get() = true |
| override val list: NodeList? get() = null |
| override fun dispose() = (job as JobSupport).removeNode(this) |
| } |
| |
| internal class NodeList : LockFreeLinkedListHead(), Incomplete { |
| override val isActive: Boolean get() = true |
| override val list: NodeList get() = this |
| |
| fun getString(state: String) = buildString { |
| append("List{") |
| append(state) |
| append("}[") |
| var first = true |
| this@NodeList.forEach<JobNode<*>> { node -> |
| if (first) first = false else append(", ") |
| append(node) |
| } |
| append("]") |
| } |
| |
| override fun toString(): String = getString("Active") |
| } |
| |
| internal class InactiveNodeList( |
| override val list: NodeList |
| ) : Incomplete { |
| override val isActive: Boolean get() = false |
| override fun toString(): String = list.getString("New") |
| } |
| |
| private class InvokeOnCompletion( |
| job: Job, |
| private val handler: CompletionHandler |
| ) : JobNode<Job>(job) { |
| override fun invoke(cause: Throwable?) = handler.invoke(cause) |
| override fun toString() = "InvokeOnCompletion[$classSimpleName@$hexAddress]" |
| } |
| |
| private class ResumeOnCompletion( |
| job: Job, |
| private val continuation: Continuation<Unit> |
| ) : JobNode<Job>(job) { |
| override fun invoke(cause: Throwable?) = continuation.resume(Unit) |
| override fun toString() = "ResumeOnCompletion[$continuation]" |
| } |
| |
| internal class DisposeOnCompletion( |
| job: Job, |
| private val handle: DisposableHandle |
| ) : JobNode<Job>(job) { |
| override fun invoke(cause: Throwable?) = handle.dispose() |
| override fun toString(): String = "DisposeOnCompletion[$handle]" |
| } |
| |
| private class SelectJoinOnCompletion<R>( |
| job: JobSupport, |
| private val select: SelectInstance<R>, |
| private val block: suspend () -> R |
| ) : JobNode<JobSupport>(job) { |
| override fun invoke(cause: Throwable?) { |
| if (select.trySelect(null)) |
| block.startCoroutineCancellable(select.completion) |
| } |
| override fun toString(): String = "SelectJoinOnCompletion[$select]" |
| } |
| |
| private class SelectAwaitOnCompletion<T, R>( |
| job: JobSupport, |
| private val select: SelectInstance<R>, |
| private val block: suspend (T) -> R |
| ) : JobNode<JobSupport>(job) { |
| override fun invoke(cause: Throwable?) { |
| if (select.trySelect(null)) |
| job.selectAwaitCompletion(select, block) |
| } |
| override fun toString(): String = "SelectAwaitOnCompletion[$select]" |
| } |
| |
| // -------- invokeOnCancellation nodes |
| |
| /** |
| * Marker for node that shall be invoked on in _failing_ state. |
| * **Note: may be invoked multiple times.** |
| */ |
| internal abstract class JobFailingNode<out J : Job>(job: J) : JobNode<J>(job) |
| |
| private class InvokeOnFailing( |
| job: Job, |
| private val handler: CompletionHandler |
| ) : JobFailingNode<Job>(job) { |
| // delegate handler shall be invoked at most once, so here is an additional flag |
| private val _invoked = atomic(0) // todo: replace with atomic boolean after migration to recent atomicFu |
| override fun invoke(cause: Throwable?) { |
| if (_invoked.compareAndSet(0, 1)) handler.invoke(cause) |
| } |
| override fun toString() = "InvokeOnFailing[$classSimpleName@$hexAddress]" |
| } |
| |
| internal class ChildJob( |
| parent: JobSupport, |
| @JvmField val childJob: Job |
| ) : JobFailingNode<JobSupport>(parent) { |
| override fun invoke(cause: Throwable?) = childJob.cancelChild(job) |
| override fun toString(): String = "ChildJob[$childJob]" |
| } |
| |
| // Same as ChildJob, but for cancellable continuation |
| internal class ChildContinuation( |
| parent: Job, |
| @JvmField val child: AbstractContinuation<*> |
| ) : JobFailingNode<Job>(parent) { |
| override fun invoke(cause: Throwable?) { |
| child.cancel(job.getCancellationException()) |
| } |
| override fun toString(): String = |
| "ChildContinuation[$child]" |
| } |
| |