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StampedLock内部实现时，使用类似于CAS操作的死循环反复尝试的策略。在它挂起线程时，使用的是Unsafe.park()函数，而park()函数在遇到线程中断时，会直接返回（注意，不同于Thread.sleep()方法，他不会抛出异常）。而在StampedLock的死循环逻辑中，没有处理有关中断的逻辑。因此，这就会导致阻塞在park()方法上的线程被中断后，再次进入循环。而当退出条件得不到满足时，就会发生疯狂占用CPU的情况。演示代码如下：

package com.aden.powoms.biz.drgcompute.compute.biz.impl;

import java.util.concurrent.locks.LockSupport;
import java.util.concurrent.locks.StampedLock;

/**
 * StampedLock 的小陷阱Demo
 */
public class StampedLockCPUDemo {

    private static Thread[] holdCpuThreads = new Thread[3];
    private static StampedLock lock = new StampedLock();

    public static void main(String[] args) throws InterruptedException {
        new Thread(){
            @Override
            public void run() {
                long readLong = lock.writeLock();
                LockSupport.parkNanos(600000000000L);
                lock.unlockWrite(readLong);
            }
        }.start();

        Thread.sleep(1000);
		// 线程中断后，会占用CPU
        for(int i = 0; i < 3; ++ i){
            holdCpuThreads[i] = new Thread(new HoldCPUReadThread());
            holdCpuThreads[i].start();
        }
    }

    private static class HoldCPUReadThread implements Runnable {

        @Override
        public void run() {
            long locker = lock.readLock();
            System.out.println(Thread.currentThread().getName() + " 获得读锁");
            lock.unlockRead(locker);
        }
    }
}