Java 更改线程池中一个线程的延迟

我向我的线程池添加了三个具有不同任务和不同延迟的线程，一切都很好

static ScheduledExecutorService scheduleTaskExecutor;
static ScheduledFuture<?> future1;
static ScheduledFuture<?> future2;
static ScheduledFuture<?> future3;

public void onCreate(Bundle savedInstanceState) {
    scheduleTaskExecutor = Executors.newScheduledThreadPool(3);
    future1 = scheduleTaskExecutor.scheduleWithFixedDelay(new Runnable1() {...}, 0, olddelay1, TimeUnit.SECONDS); // Task 1
    future2 = scheduleTaskExecutor.scheduleWithFixedDelay(new Runnable2() {...}, 0, olddelay2, TimeUnit.SECONDS); // Task 2
    future3 = scheduleTaskExecutor.scheduleWithFixedDelay(new Runnable3() {...}, 0, olddelay3, TimeUnit.SECONDS); // Task 3
}

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那么，是否有可能只更改一个线程的延迟呢？

您的操作与您所做的完全相同-您的代码中一定存在其他错误

这里有一个完整的工作示例，它与您正在做的事情相同。下面的输出显示它正在按预期工作

public class Reschedule {

    public static void main(String[] args) throws InterruptedException {
        long start = System.currentTimeMillis();
        ScheduledExecutorService executor = Executors.newSingleThreadScheduledExecutor();

        // Schedule three tasks
        ScheduledFuture future1 = executor.scheduleAtFixedRate(() -> {
            System.out.printf("%03ds: This is the first runnable, reporting in%n", (System.currentTimeMillis() - start) / 1000);
        }, 0, 5, TimeUnit.SECONDS);
        ScheduledFuture future2 = executor.scheduleAtFixedRate(() -> {
            System.out.printf("%03ds: This is the second runnable, reporting in%n", (System.currentTimeMillis() - start) / 1000);
        }, 2, 10, TimeUnit.SECONDS);
        ScheduledFuture future3 = executor.scheduleAtFixedRate(() -> {
            System.out.printf("%03ds: This is the third runnable, reporting in%n", (System.currentTimeMillis() - start) / 1000);
        }, 5, 15, TimeUnit.SECONDS);

        // Wait some
        Thread.sleep(30000);

        // Reschedule the second task
        System.out.printf("%03ds: Rescheduling the second runnable to run at 20 second intervals%n", (System.currentTimeMillis() - start) / 1000);
        future2.cancel(true);
        future2 = executor.scheduleAtFixedRate(() -> {
            System.out.printf("%03ds: This is the second runnable, reporting in%n", (System.currentTimeMillis() - start) / 1000);
        }, 2, 20, TimeUnit.SECONDS);
    }
}

正如您在下面的输出中所看到的，重新安排第二个任务会将其重置，并将其从每10秒运行一次更改为每20秒运行一次，并且第一个和第三个任务不受影响

输出：

---

你似乎把任务和线程混淆了。你不需要在你的线程池中有和你有任务一样多的线程，除非你的任务真的非常繁重，你只需要一个线程就可以了。此外，您如何知道executor中只计划了1个任务？我可以在日志文件中看到它。好的，我想你是对的。我把任务和线程搞混了。因此Executors.newScheduledThreadPool（1）也可以工作。但是有可能改变一项任务的延迟吗？

public class Reschedule {

    public static void main(String[] args) throws InterruptedException {
        long start = System.currentTimeMillis();
        ScheduledExecutorService executor = Executors.newSingleThreadScheduledExecutor();

        // Schedule three tasks
        ScheduledFuture future1 = executor.scheduleAtFixedRate(() -> {
            System.out.printf("%03ds: This is the first runnable, reporting in%n", (System.currentTimeMillis() - start) / 1000);
        }, 0, 5, TimeUnit.SECONDS);
        ScheduledFuture future2 = executor.scheduleAtFixedRate(() -> {
            System.out.printf("%03ds: This is the second runnable, reporting in%n", (System.currentTimeMillis() - start) / 1000);
        }, 2, 10, TimeUnit.SECONDS);
        ScheduledFuture future3 = executor.scheduleAtFixedRate(() -> {
            System.out.printf("%03ds: This is the third runnable, reporting in%n", (System.currentTimeMillis() - start) / 1000);
        }, 5, 15, TimeUnit.SECONDS);

        // Wait some
        Thread.sleep(30000);

        // Reschedule the second task
        System.out.printf("%03ds: Rescheduling the second runnable to run at 20 second intervals%n", (System.currentTimeMillis() - start) / 1000);
        future2.cancel(true);
        future2 = executor.scheduleAtFixedRate(() -> {
            System.out.printf("%03ds: This is the second runnable, reporting in%n", (System.currentTimeMillis() - start) / 1000);
        }, 2, 20, TimeUnit.SECONDS);
    }
}

000s: This is the first runnable, reporting in
002s: This is the second runnable, reporting in
005s: This is the first runnable, reporting in
005s: This is the third runnable, reporting in
010s: This is the first runnable, reporting in
012s: This is the second runnable, reporting in
015s: This is the first runnable, reporting in
020s: This is the first runnable, reporting in
020s: This is the third runnable, reporting in
022s: This is the second runnable, reporting in
025s: This is the first runnable, reporting in
030s: This is the first runnable, reporting in
030s: Rescheduling the second runnable to run at 20 second intervals
032s: This is the second runnable, reporting in
035s: This is the first runnable, reporting in
035s: This is the third runnable, reporting in
040s: This is the first runnable, reporting in
045s: This is the first runnable, reporting in
050s: This is the first runnable, reporting in
050s: This is the third runnable, reporting in
052s: This is the second runnable, reporting in
055s: This is the first runnable, reporting in
060s: This is the first runnable, reporting in
065s: This is the first runnable, reporting in
065s: This is the third runnable, reporting in
070s: This is the first runnable, reporting in
072s: This is the second runnable, reporting in