延迟启动的单线程

Question

我想做的是：按一个按钮更改简单值。如果值在 3 秒内保持不变，我想执行我的方法。所以我需要一个线程，它会在每次单击按钮时启动（并杀死所有其他线程）。我知道

Executor executor = Executors.newSingleThreadScheduledExecutor();

但它不能有延迟。这样做的最佳做法是什么？

Answer 1

您可以简单地使用旧的 Thread class 或 Runnable 界面：单击按钮后立即启动线程，执行 Thread.sleep(3000) 作为第一条指令，然后检查该值是否未更改。在启动线程之前检查是否已经存在另一个线程，如果存在，调用 interrupt() 并处理 InterruptedException 以优雅地终止它。

如果你想使用较新的并发 API，请注意 Executors.newSingleThreadScheduledExecutor() returns a ScheduledExecutorService（不是简单的 Executor）并且它允许顾名思义，延迟启动线程。检查 Javadoc.

Answer 2

要么你可以使用简单的 Thread start-stop/interrupt，要么你可以使用 API 之类的 ScheduledExecutorService。
下面是如何使用 ScheduledExecutorService 的示例

//Start as many threads as you want upon button click... (since you said i want to kill all other threads, so i assume you want to start some threads soon upon button click)
            ScheduledExecutorService service = Executors.newScheduledThreadPool(3);
            service.schedule(new Thread(), 0, TimeUnit.SECONDS);
            service.schedule(new Thread(), 0, TimeUnit.SECONDS);
            service.schedule(new Thread(), 0, TimeUnit.SECONDS);

            //Start single thread after 3 seconds.
            ScheduledExecutorService serviceCheck = Executors.newScheduledThreadPool(3);
            serviceCheck.schedule(new Thread(), 3, TimeUnit.SECONDS);
            //In this thread created using "serviceCheck", check with value has not changed then use `service.shutdownNow();` to shutdown all previously started threads and then do whatever you want.

延迟启动的单线程

Single thread with a delay to start

java

single-threaded