Java Thread Async ... / SpringBoot Scheduler

Java Thread Tool Kit

Callable / Future / FutureTask

```java= public class CallableAndFuture { static class Task implements Callable { @Override public String call() throws Exception { return "Hello world"; } }

public static void main(String[] args) {
    ExecutorService threadPool = Executors.newSingleThreadExecutor();
    Future<String> future = threadPool.submit(new Task());
System.out.println(future.get());

    Task task = new Task();
    FutureTask<Integer> futureTask = new FutureTask<Integer>(task);
    executor.submit(futureTask);
    System.out.println("task运行结果"+futureTask.get());
}

}

> FutureTask 可以call cancel

### CountDownLatch
```java=
    ExecutorService es = Executors.newFixedThreadPool(5);
    try {
      CountDownLatch cdt = new CountDownLatch(5);

      for (int i = 0; i < 5; i++) {
        es.execute(()->{
            cdt.countDown();
        });
      }
      cdt.await();
      System.out.println("thread running finish");
    } catch(Exception e) {
      throw new RuntimeException(e);
    } finally {
      es.shutdown();
    }

SpringBoot Scheduler

Runtime

```java=

@Inject
private TaskScheduler scheduler;

... // Runtime start scheduler ScheduledFuture scheduledFuture = s.schedule(this, new CronTrigger("0 0/5 * * * *")); //取消 Runtime scheduler scheduledFuture.cancel(true);

```

tags: java springboot