深入理解Java虚拟机：JVM高级特性与最佳实践（第3版）第12章 Java内存模型与线程

public class C12D1 {

    public static volatile int race = 0;

    public static void increase() {
        race++;
    }

    private static final int THREADS_COUNT = 20;

    public static void main(String[] args) {

        CountDownLatch countDownLatch = new CountDownLatch(THREADS_COUNT);

        Thread[] threads = new Thread[THREADS_COUNT];

        for (int i = 0; i < THREADS_COUNT; i++) {
            threads[i] = new Thread(() -> {

                try {
                    for (int j = 0; j < 10000; j++) {
                        increase();
                    }
                } finally {
                    countDownLatch.countDown();
                }
            });
            threads[i].start();
        }

        try {
            countDownLatch.await();
        } catch (InterruptedException e) {
            e.printStackTrace();
        }
        System.out.println(race);
    }
}
-------
36654