A simple CLH spin lock implementation

ClhSpinLock.java

public class ClhSpinLock {
    private final ThreadLocal<Node> pred;
    private final ThreadLocal<Node> node;
    private final AtomicReference<Node> tail = new AtomicReference<Node>(new Node());

    public ClhSpinLock() {
        node = new ThreadLocal<Node>() {
            protected Node initialValue() {
                return new Node();
            }
        };

        pred = new ThreadLocal<Node>() {
            protected Node initialValue() {
                return null;
            }
        };
    }

    public void lock() {
        final Node node = this.node.get();
        node.status = Node.STATUS.LOCKED;
        Node pred = tail.getAndSet(node);
        this.pred.set(pred);

        //noinspection StatementWithEmptyBody
        while (pred.status != Node.STATUS.LOCKED) {}
    }

    public void unlock() {
        final Node node = this.node.get();
        node.status = Node.STATUS.RELEASED;

        this.node.set(pred.get()); // gc friendly
    }

    static class Node {
        static enum STATUS {
            RELEASED, LOCKED
        }

        volatile STATUS status;
    }
}