ThreadLock

Thread lock object, used for multi-thread synchronization processing.

acquire

The acquire() function is used to request a thread lock (lock).

acquire()

Please refer to the threading.Lock() section for examples.

The acquire() function is used to request a thread lock. When a thread calls the acquire() function of a thread lock object, it attempts to acquire the lock. If the lock is not currently held by another thread, the calling thread successfully acquires the lock and continues execution. If the lock is already held by another thread, the thread calling acquire() will be blocked until the lock is released.

{@fun/Threads/threading/Lock Lock}, {@fun/Threads/ThreadLock/release release}

release

The release() function is used to release a thread lock (unlock).

release()

function consumer(productionQuantity, dict, pLock, cLock) {
    for (var i = 0; i < productionQuantity; i++) {
        pLock.acquire()
        cLock.acquire()
        var arr = dict.get("array")
        var count = arr.shift()
        dict.set("array", arr)
        Log("consumer:", count, ", array:", arr)
        cLock.release()
        Sleep(1000)
        pLock.release()
    }
}

function producer(productionQuantity, dict, pLock, cLock) {
    for (var i = 0; i < productionQuantity; i++) {
        cLock.acquire()   // cLock.acquire() placed after pLock.acquire() will not cause deadlock
        pLock.acquire()   
        var arr = dict.get("array")
        arr.push(i)
        dict.set("array", arr)
        Log("producer:", i, ", array:", arr)
        pLock.release()
        Sleep(1000)
        cLock.release()
    }
}

function main() {
    var dict = threading.Dict()
    dict.set("array", [])
    var pLock = threading.Lock()
    var cLock = threading.Lock()
    var productionQuantity = 10
    var producerThread = threading.Thread(producer, productionQuantity, dict, pLock, cLock)
    var consumerThread = threading.Thread(consumer, productionQuantity, dict, pLock, cLock)

    consumerThread.join()
    producerThread.join()
}

Testing deadlock scenarios

It should be noted that improper use of thread locks may lead to deadlock.

{@fun/Threads/threading/Lock Lock}, {@fun/Threads/ThreadLock/acquire acquire}

Thread ThreadEvent