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This article introduces the knowledge of "what is AbstractQueuedSynchronizer". In the operation of actual cases, many people will encounter such a dilemma. Then let the editor lead you to learn how to deal with these situations. I hope you can read it carefully and be able to achieve something!

AbstractQueuedSynchronizer Abstract Class

Implement the following methods alone in the subclass

* {@ link # tryAcquire} * {@ link # tryRelease} * {@ link # tryAcquireShared} * {@ link # tryReleaseShared} * {@ link # isHeldExclusively}

State status modification uses the following methods

{@ link # getState}, {@ link* # setState} {@ link # compareAndSetState}:

Node {

/ / indicates the node status, CANCELLED. A value of 1 indicates that the current thread is canceled. The SIGNAL value is-1.

/ / indicates that the successor node of the current node contains threads that need to be run, that is, unpark

/ / the condition value is-2, which means that the current node is waiting for condition, that is, condition queue.

/ / propagate. The value is-3, which means that subsequent acquireShared in the current scene can be executed.

/ / the value is 0, indicating that the current node is in the sync queue, waiting to acquire the lock

Int waitStatus

/ / precursor node. If you cancel the current node, you need to complete the connection.

Node prev

/ / successor node

Node next

/ / Store the successor nodes in the condition queue

Node nextWaiter

/ / the current thread queued

Thread thread

}

/ / get an exclusive lock

While (acquire Lock) {

If (obtained) {

Exit the while loop

} else {

If (the current thread is not queued) {

Then join the queue.

}

Block the current thread

}

}

}

}

/ / release an exclusive lock

If (released successfully) {

Delete header node

Activate the successor node of the original header node

}

That's all for "what AbstractQueuedSynchronizer is". Thank you for your reading. If you want to know more about the industry, you can follow the website, the editor will output more high-quality practical articles for you!

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