合影留恋

@fiypig 替我一个朋友问下，私人兼职都是怎么联系上的

用原子变量%3 这种解法比较常见，但是需要线程忙等，提供一种用线程池方式实现的思路：

public static void main(String[] args) throws InterruptedException {
ExecutorService executorService1 = Executors.newSingleThreadExecutor();
ExecutorService executorService2 = Executors.newSingleThreadExecutor();
ExecutorService executorService3 = Executors.newSingleThreadExecutor();

Runnable[] rs = new Runnable[3];

rs[0] = () -> {
System.out.println("A");
executorService2.submit(rs[1]);
};

rs[1] = () -> {
System.out.println("B");
executorService2.submit(rs[2]);
};

rs[2] = new Runnable() {
private int a = 1;

public void run() {
System.out.println("C");
if (a++ < 100)
executorService3.submit(rs[0]);
}
};

executorService1.submit(rs[0]);
}