swift3.0-信号量、group、barrier
3921 ワード
//
// ViewController.swift
//
//
// Created by houjianan on 2017/2/27.
// Copyright © 2017 houjianan. All rights reserved.
//
import UIKit
class ViewController: UIViewController {
override func viewDidLoad() {
super.viewDidLoad()
// group
// notify
// notify
// 6 3
let queue = DispatchQueue.global(qos: .default)
let group = DispatchGroup()
let sem = DispatchSemaphore(value: 0)
queue.async(group: group, execute: {
print(1)
queue.asyncAfter(deadline: DispatchTime.now() + Double(Int64(3 * 1000 * 1000000)) / Double(NSEC_PER_SEC), execute: {
sem.signal()
print(6)
})
sem.wait()
})
queue.async(group: group, execute: {
print(2)
})
queue.async(group: group, execute: {
print(3)
})
group.notify(queue: queue, execute: {
print(5)
})
// group enter() leave()
// notify
let queue = DispatchQueue.global(qos: .default)
let group = DispatchGroup()
group.enter()
queue.async(group: group, execute: {
print(1)
queue.asyncAfter(deadline: DispatchTime.now() + Double(Int64(3 * 1000 * 1000000)) / Double(NSEC_PER_SEC), execute: {
print(6)
group.leave()
})
})
group.enter()
queue.async(group: group, execute: {
queue.asyncAfter(deadline: DispatchTime.now() + Double(Int64(3 * 1000 * 1000000)) / Double(NSEC_PER_SEC), execute: {
print(2)
group.leave()
})
})
group.enter()
queue.async(group: group, execute: {
queue.asyncAfter(deadline: DispatchTime.now() + Double(Int64(3 * 1000 * 1000000)) / Double(NSEC_PER_SEC), execute: {
print(3)
group.leave()
})
})
group.notify(queue: queue, execute: {
print(4)
})
// group
let queue = DispatchQueue.global(qos: .default)
let group = DispatchGroup()
let sem = DispatchSemaphore(value: 0)
queue.async(group: group, execute: {
queue.asyncAfter(deadline: DispatchTime.now() + Double(Int64(3 * 1000 * 1000000)) / Double(NSEC_PER_SEC), execute: {
sem.signal()
print(1)
sem.wait()
})
})
queue.async(group: group, execute: {
queue.asyncAfter(deadline: DispatchTime.now() + Double(Int64(3 * 1000 * 1000000)) / Double(NSEC_PER_SEC), execute: {
sem.signal()
print(2)
sem.wait()
})
})
queue.async(group: group, execute: {
queue.asyncAfter(deadline: DispatchTime.now() + Double(Int64(3 * 1000 * 1000000)) / Double(NSEC_PER_SEC), execute: {
sem.signal()
print(3)
sem.wait()
})
})
group.notify(queue: queue, execute: {
sem.signal()
print(7)
sem.wait()
})
// barrier
let dataQueue = DispatchQueue(label: "data", attributes: .concurrent)
let write = DispatchWorkItem(flags: .barrier) {
dataQueue.asyncAfter(deadline: DispatchTime.now() + Double(Int64(3 * 1000 * 1000000)) / Double(NSEC_PER_SEC), execute: {
print(2.1)
})
print(2)
Thread.sleep(forTimeInterval: 5)
}
dataQueue.async {
print(1)
}
dataQueue.async(execute: write)
dataQueue.async {
print(3)
}
}
}