31 lines
879 B
Java
31 lines
879 B
Java
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package threaddemo.lock;
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import java.util.concurrent.atomic.AtomicReference;
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/**
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* demo class for CLH. code from
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* <a href="https://mp.weixin.qq.com/s/jEx-4XhNGOFdCo4Nou5tqg">Java AQS 核心数据结构-CLH 锁</a>
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* This is only for demo, do not run the code this node class is not workable
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*/
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public class CLH {
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private final ThreadLocal<Node> node = ThreadLocal.withInitial(Node::new);
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private final AtomicReference<Node> tail = new AtomicReference<>(new Node());
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private static class Node {
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private volatile boolean locked;
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}
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private void lock() {
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Node node = this.node.get();
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node.locked = true;
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Node pre = this.tail.getAndSet(node);
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while (!pre.locked) ;
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}
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private void unlock() {
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final Node node = this.node.get();
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node.locked = false;
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this.node.set(new Node());
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}
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}
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