CopyOnWriteArraySet ，executorService.shutdown()，executorService.isTerminated()的使用

    public static void main(String[] args) {
        long startTime = System.currentTimeMillis();
        Set<String> str = new CopyOnWriteArraySet<String>();
        ExecutorService executorService = Executors.newFixedThreadPool(57);
        for(int i=0;i<10000;i++){
            int finalI = i;
            executorService.submit(()->{
                try {
                    Thread.sleep(1l);
                } catch (InterruptedException e) {
                    e.printStackTrace();
                }
                //System.out.println("huqi"+finalI+Thread.currentThread().getName());
                str.add("huqi"+ finalI);
            });
        }
        // 顺序的停止线程
        executorService.shutdown();
　　　　　//判断是否所有的线程已经运行完
        while (!executorService.isTerminated()) {
            try {
                executorService.awaitTermination(5, TimeUnit.SECONDS);
            } catch (InterruptedException e) {
                e.printStackTrace();
            }
        }
        long endTime = System.currentTimeMillis();
        System.out.println(str.size());
        System.out.println(endTime-startTime);
    }