手写一个ReentrantLock，包括AQS_手写reentrantlock的aqs

继承AQS

public class ReentrantLockUseAQS extends AbstractQueuedSynchronizer {
   

    @Override
    protected boolean tryAcquire(int arg) {
   
        if (compareAndSetState(0,1)) {
   
            setExclusiveOwnerThread(Thread.currentThread());
            return true;
        }
        return false;
    }


    @Override
    protected boolean tryRelease(int arg) {
   
        if (compareAndSetState(1,0)) {
   
            setExclusiveOwnerThread(null);
            return true;
        }
        return false;
    }

    public static void main(String[] args) {
   
        final ReentrantLockUseAQS lock = new ReentrantLockUseAQS();

        new Thread(() -> {
   
            // 获取锁
            lock.acquire(1);
            System.out.println("T1成功获取锁," + LocalDateTime.now());
            try {
   
                TimeUnit.SECONDS.sleep(3);
                System.out.println("T1执行完毕");
            } catch (InterruptedException e) {
   
                e.printStackTrace();
            }finally {
   
                // 释放锁
                lock.release(1);
                System.out.println("T1释放了锁，" + LocalDateTime.now());
            }
        },"T1").start();

        new Thread(() -> {
   
            try {
   
                // 让T1先获取锁
                TimeUnit.SECONDS.sleep(1);
            } catch (InterruptedException e) {
   
                e.printStackTrace();
            }
            lock.acquire(1);
            System.out.println("T2获取到锁," + LocalDateTime.now());
            lock.release(1);
        },"T2").start();
    }
}
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用自己实现的AQS

1. acquire思路：需要获取锁的线程不断去轮询获取锁，多次获取不到则放入到队尾且park，等待其他线程唤醒，被唤醒后继续去获取锁，若获取到则继续往下执行
2. release思路：释放自己持有的锁，唤醒下一个线程节点去争抢锁
3. 如何保证线程安全：使用Java自带的Unsafe的CAS控制

/**
 * 模仿AQS写的锁
 * 底层主要是LockSupport进行park跟unpark
 * 使用Unsafe的CAS保证修改变量的原子性
 */
public 
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