[Swift] GCD関連 [Swift4対応]

  • キューの作成

(Swift2まで)

let queue1 = dispatch_queue_create("arrayQ", DISPATCH_QUEUE_SERIAL)
let queue2 = dispatch_queue_create("arrayQ", DISPATCH_QUEUE_CONCURRENT)

(Swift3以降)

let queue1 = DispatchQueue(label: "arrayQ")
let queue2= DispatchQueue(label: "arrayQ", attributes: .concurrent)

(Swift2まで)

let queue3 = dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_BACKGROUND, 0)
let queue4 = dispatch_get_main_queue()

(Swift3以降)

let queue3 = DispatchQueue.global(qos:DispatchQoS.QoSClass.background)
let queue4= DispatchQueue.main

  • グループの作成

(Swift2まで)

let group = dispatch_group_create()

(Swift3以降)

let group = DispatchGroup()

  • グループのwait

(Swift2まで)

dispatch_group_wait(group, dispatch_time_t(DISPATCH_TIME_FOREVER))

(Swift3以降)

group.wait(wallTimeout: .distantFuture)

  • 同期処理

(Swift2まで)

dispatch_sync(queue, {() in
...
}

(Swift3以降)

queue.sync {() in
...
}

  • 非同期処理

(Swift2まで)

dispatch_async(queue, {() in
...
}

(Swift3以降)

queue.async {() in
...
}

(Swift2まで)

dispatch_barrier_async(queue, {() in
...
}

(Swift3以降)

queue.async(flags: .barrier) {() in
...
}

  • セマフォ宣言

(Swift2まで)

let semaphore:dispatch_semaphore_t

(Swift3以降)

let semaphore:DispatchSemaphore

  • セマフォの作成

(Swift2まで)

semaphore = dispatch_semaphore_create(Int)

(Swift3以降)

semaphore = DispatchSemaphore(value: Int)

  • セマフォのwait

(Swift2まで)

if (dispatch_semaphore_wait(semaphore, DISPATCH_TIME_FOREVER) == 0) {
...
}

(Swift3以降)

if (semaphore.wait(timeout:.distantFuture) == .success) {
...
}

  • セマフォのsignal

(Swift2まで)

dispatch_semaphore_signal(semaphore)

(Swift3以降)

semaphore.signal()