public class ABADemo {
    static AtomicReference<Integer> atomicReference = new AtomicReference<>(100);
    static AtomicStampedReference<Integer> atomicStampedReference = new AtomicStampedReference<>(100, 1);
    public static void main(String[] args) {
        System.out.println("=================以下时ABA问题的产生=================");
        new Thread(() -> {
            atomicReference.compareAndSet(100, 101);
            atomicReference.compareAndSet(101, 100);
        }, "t1").start();

        new Thread(() -> {
            //睡 1s 保证t1线程已经执行完
            try{ TimeUnit.SECONDS.sleep(1); } catch (InterruptedException e){ e.printStackTrace(); }
            System.out.println(atomicReference.compareAndSet(100, 2019) + "\\t " + atomicReference.get());
        }, "t2").start();

        //睡 2s 保证上面两条线程已经执行完
        try{ TimeUnit.SECONDS.sleep(2); } catch (InterruptedException e){ e.printStackTrace(); }
        System.out.println("=================以下时ABA问题的解决=================");
        new Thread(() -> {
            int stamp = atomicStampedReference.getStamp();
            try{ TimeUnit.SECONDS.sleep(1); } catch (InterruptedException e){ e.printStackTrace(); }
            atomicStampedReference.compareAndSet(100, 101, stamp, stamp + 1);
            System.out.println(Thread.currentThread().getName() + "\\t 值：" + atomicStampedReference.getReference() + " 版本号：" + atomicStampedReference.getStamp());
            stamp = atomicStampedReference.getStamp();
            atomicStampedReference.compareAndSet(101, 100, stamp, stamp + 1);
            System.out.println(Thread.currentThread().getName() + "\\t 值：" + atomicStampedReference.getReference() + " 版本号：" + atomicStampedReference.getStamp());
        }, "t3").start();

        new Thread(() -> {
            //睡 1s 保证t1线程已经执行完
            try{ TimeUnit.SECONDS.sleep(3); } catch (InterruptedException e){ e.printStackTrace(); }
            int stamp = atomicStampedReference.getStamp();
            System.out.println(atomicStampedReference.compareAndSet(100, 2019, stamp, stamp + 1) + "\\t 值：" + atomicStampedReference.getReference() + " 版本号：" + stamp);
        }, "t4").start();
    }
}