当你 start 如果使用yourthread.start（）创建一个线程，系统将启动一个新线程来执行 run 方法。您可以简单地打印如下内容： System.out.println("FINISHED " + this.getName()) 在比赛结束时 run 方法。
注：请确保你没有把上面的打印放在一些循环中，它应该是最后一个语句 run 方法.execute（）方法与.start（）几乎相同）

要了解任务状态，您需要将来的示例。现在有两点：
如果您只是想知道任务是否已完成，请使用 executorService.submit(worker) ，而不是 executorService.execute(worker) 方法。
如果您还想在任务完成后获得一些结果，请使用 Callable 接口而不是 Runnable . 见以下代码：

public class A {
  public static void main(String args[]){
    ExecutorService executorService = Executors.newFixedThreadPool(5);
    Callable<String> worker = new FileUploadThread("thread");
    Future<String> workerTask = executorService.submit(worker);

    try {
        boolean isDone = workerTask.isDone();
        System.out.println("Task is done: " + isDone);

        //Wait untill task is executing
        String status = workerTask.get();

        System.out.println("Status: " + status);
        isDone = workerTask.isDone();
        System.out.println("Task is done: " + isDone);
    } catch (InterruptedException | ExecutionException e) {
        e.printStackTrace();
    }
    executorService.shutdown();
  }
}

class FileUploadThread implements Callable<String> {
  //has a parametrized constuctor
  public FileUploadThread(String thread) { }

  @Override
  public String call() throws Exception {
    for(int i=0; i<5; i++){
        System.out.println("executing..sleep for 1 sec...");
        Thread.sleep(1000);
    }
    return "DONE";
  }
}

输出：

Task is done: false
executing..sleep for 1 sec...
executing..sleep for 1 sec...
executing..sleep for 1 sec...
executing..sleep for 1 sec...
executing..sleep for 1 sec...
Status: DONE
Task is done: true

你可以用 yourThread.join() .