JAVA主线程等待所有子线程执行完后才开始执行

1 使用线程池方法：

运行效果可以看到：

2 使用countDownLatch同步工具类

CountDownLatch countDownLatch=new CountDownLatch(2);

Log.e("tanlin", "主线程开始执行");

ThreadPoolExecutor threadPoolExecutor=new ThreadPoolExecutor(10,10,0l,

        TimeUnit.MILLISECONDS,new LinkedBlockingQueue<>());

threadPoolExecutor.submit(new Runnable() {

@Override

    public void run() {

try {

Thread.sleep(1000);

            Log.e("tanlin", "子线程执行1");

            countDownLatch.countDown();

        }catch (InterruptedException e) {

e.printStackTrace();

        }

}

});

threadPoolExecutor.submit(new Runnable() {

@Override

    public void run() {

try {

Thread.sleep(1000);

            Log.e("tanlin", "子线程执行2");

            countDownLatch.countDown();

        }catch (InterruptedException e) {

e.printStackTrace();

        }

}

});

try {

countDownLatch.await();

}catch (InterruptedException e) {

e.printStackTrace();

}

Log.e("tanlin", "两个子线程执行完，主线程继续执行");

这两种方式比较优雅，当然还有其他各种方式。