swift 互斥锁lock学习

一些学习过程中的难点解决

例子

class ViewController: UIViewController {
let lock = NSLock()
var person = Person(name: "Leo", age: 23)
override func viewDidLoad() {
super.viewDidLoad()
let queue1 = dispatch_queue_create("com.test.queue1", DISPATCH_QUEUE_SERIAL)
let queue2 = dispatch_queue_create("com.test.queue1", DISPATCH_QUEUE_SERIAL)
dispatch_async(queue1) { () -> Void in
self.lock.lock()
self.person.update("queue1", delay: 2, age: 1)
self.lock.unlock()
}
dispatch_async(queue2) { () -> Void in
self.lock.lock()
self.person.update("queue2", delay: 1, age: 2)
self.lock.unlock()
}
self.performSelector("logPerson", withObject: nil, afterDelay: 4)
// Do any additional setup after loading the view, typically from a nib.
}
func logPerson(){
NSLog("%@ %d", person.name,person.age)
}

}

这样就会当执行 self.person.update(“queue2”, delay: 1, age: 2)时候锁定，执行完后释放锁，然后下一个线程才会重新调用update，这样数据不会错乱

case .Failure(let error):
if response.response?.statusCode == 401{//刷新token
dispatch_async(queue3) { () -> Void in
lock?.lock()//这里添加互斥锁，防止一起刷新token，这样就会分开之行token方法cjq
RefreshToken({ (AnyObject) in
lock?.unlock()
var hs = headers
hs!["Authorization"] = NSUserDefaults.standardUserDefaults().stringForKey("access_token")
}
}, logOut: { (NSError) in
logOut?()
lock?.unlock()
})
}
}else{
failure?(error)
}
}