fun shutdown()

in kotlinx-coroutines-core/jvm/src/scheduling/CoroutineScheduler.kt [368:406]

• 29 lines of code
• 6 McCabe index (conditional complexity)

    fun shutdown(timeout: Long) {
        // atomically set termination flag which is checked when workers are added or removed
        if (!_isTerminated.compareAndSet(false, true)) return
        // make sure we are not waiting for the current thread
        val currentWorker = currentWorker()
        // Capture # of created workers that cannot change anymore (mind the synchronized block!)
        val created = synchronized(workers) { createdWorkers }
        // Shutdown all workers with the only exception of the current thread
        for (i in 1..created) {
            val worker = workers[i]!!
            if (worker !== currentWorker) {
                // Note: this is java.lang.Thread.getState() of type java.lang.Thread.State
                while (worker.getState() != Thread.State.TERMINATED) {
                    LockSupport.unpark(worker)
                    worker.join(timeout)
                }
                // Note: this is CoroutineScheduler.Worker.state of type CoroutineScheduler.WorkerState
                assert { worker.state === WorkerState.TERMINATED } // Expected TERMINATED state
                worker.localQueue.offloadAllWorkTo(globalBlockingQueue) // Doesn't actually matter which queue to use
            }
        }
        // Make sure no more work is added to GlobalQueue from anywhere
        globalBlockingQueue.close()
        globalCpuQueue.close()
        // Finish processing tasks from globalQueue and/or from this worker's local queue
        while (true) {
            val task = currentWorker?.findTask(true)
                ?: globalCpuQueue.removeFirstOrNull()
                ?: globalBlockingQueue.removeFirstOrNull()
                ?: break
            runSafely(task)
        }
        // Shutdown current thread
        currentWorker?.tryReleaseCpu(WorkerState.TERMINATED)
        // check & cleanup state
        assert { availableCpuPermits == corePoolSize }
        parkedWorkersStack.value = 0L
        controlState.value = 0L
    }