Playframework + Akka：如何避免在关闭应用程序时激活执行的计划任务(Playframework + Akka: how to avoid excuting scheduled tasks executed when shutdown application)

 我在调试应用程序服务器启动时启动了调度程序的问题，但是一旦应用程序关闭，它就会触及以下部分代码： 
 
// firstDay something like 1 = monday 
private void startScheduler(final ImageService imageService,
                            final ActorSystem system) {
    startImagesCleanupScheduler(imageService, system);
    Logger.info("Schedulers started");
}
 
 我的问题是Runnable块立即开始执行而不是取消任务。 
 
 澄清代码： 
 
 以下方法启动Scheduler ： 
 
private void startImagesCleanupScheduler(ImageService imageService, ActorSystem system) {
    system.scheduler().schedule(
            Duration.create(0, TimeUnit.MILLISECONDS), //Initial delay
            Duration.create(1, TimeUnit.DAYS),     //Frequency 1 days
            () -> {
                int rows = imageService.cleanupInactiveImages();
                Logger.info(String.format("%d inactive unused images cleaned from db", rows));

            },
            system.dispatcher()
    );
}
 
 我关机时的日志请注意这里的第一行： 
 
[info] - application - 1 inactive unused images cleaned from db
[info] - application - Shutting down connection pool.
[info] - application - Creating Pool for datasource 'default'
...
[info] - application - Schedulers started
[info] - play.api.Play - Application started (Prod)
 
 您可以看到它执行Scheduler忽略其原始执行时间，然后关闭，然后启动，然后“Schedulers started”。 
 
 问题是，如何取消调度程序或阻止播放在关机前运行？ 这是Akka的错误吗？ 
 
 我在OnStartup调用startScheduler ，就像下面问题的答案一样： 
 
 java Playframework对于onStart的GlobalSettings弃用 
 
 编辑：以下重现问题的最小代码： 
 
 首先创建OnStartup类： 
 
@Singleton
public class OnStartup {

    @Inject
    public OnStartup(final ActorSystem system) {
        startScheduler(system);
    }

    private void startScheduler(final ActorSystem system) {
        startImagesCleanupScheduler(system);
        Logger.info("Schedulers started");
    }

    private void startImagesCleanupScheduler(ActorSystem system) {
        system.scheduler().schedule(
                Duration.create(0, TimeUnit.MILLISECONDS), //Initial delay
                Duration.create(1, TimeUnit.DAYS),     //Frequency 1 days
                () -> {
                    //int rows = imageService.cleanupInactiveImages();
                    rows = 1;
                    Logger.info(String.format("%d inactive unused images cleaned from db", rows ));
                },
                system.dispatcher()
        );
    }

}
 
 然后创建模块： 
 
public class OnStartupModule extends AbstractModule {
    @Override
    public void configure() {
        bind(OnStartup.class).asEagerSingleton();
    }
}
 
 最后在application.conf中启用模块： 
 
play.modules.enabled += "modules.OnStartupModule"

I have issue with scheduler that I start when the play application server start, but once application got shutdown, its hit the following part of code : 
 
// firstDay something like 1 = monday 
private void startScheduler(final ImageService imageService,
                            final ActorSystem system) {
    startImagesCleanupScheduler(imageService, system);
    Logger.info("Schedulers started");
}
 
My problem that the Runnable block start to execute immediately instead of just cancel the task.
 
To clarify code:
 
The following method to start the Scheduler: 
 
private void startImagesCleanupScheduler(ImageService imageService, ActorSystem system) {
    system.scheduler().schedule(
            Duration.create(0, TimeUnit.MILLISECONDS), //Initial delay
            Duration.create(1, TimeUnit.DAYS),     //Frequency 1 days
            () -> {
                int rows = imageService.cleanupInactiveImages();
                Logger.info(String.format("%d inactive unused images cleaned from db", rows));

            },
            system.dispatcher()
    );
}
 
The log when I shutdown note the first line here :
 
[info] - application - 1 inactive unused images cleaned from db
[info] - application - Shutting down connection pool.
[info] - application - Creating Pool for datasource 'default'
...
[info] - application - Schedulers started
[info] - play.api.Play - Application started (Prod)
 
You can see it executed the Scheduler ignoring its original execution time, then got shutting down, and then started, and "Schedulers started" after.
 
What the problem, how I cancel the scheduler or prevent the play to run it before shutdown? is it a bug for Akka?
 
I'm calling startScheduler inside OnStartup like the answer of the following question :
 
java Playframework GlobalSettings deprecation for onStart
 
Edit: The following the minimal code to reproduce issue:
 
First Create OnStartup class:
 
@Singleton
public class OnStartup {

    @Inject
    public OnStartup(final ActorSystem system) {
        startScheduler(system);
    }

    private void startScheduler(final ActorSystem system) {
        startImagesCleanupScheduler(system);
        Logger.info("Schedulers started");
    }

    private void startImagesCleanupScheduler(ActorSystem system) {
        system.scheduler().schedule(
                Duration.create(0, TimeUnit.MILLISECONDS), //Initial delay
                Duration.create(1, TimeUnit.DAYS),     //Frequency 1 days
                () -> {
                    //int rows = imageService.cleanupInactiveImages();
                    rows = 1;
                    Logger.info(String.format("%d inactive unused images cleaned from db", rows ));
                },
                system.dispatcher()
        );
    }

}
 
Then create module: 
 
public class OnStartupModule extends AbstractModule {
    @Override
    public void configure() {
        bind(OnStartup.class).asEagerSingleton();
    }
}
 
Finally enable module in application.conf : 
 
play.modules.enabled += "modules.OnStartupModule"

原文：https://stackoverflow.com/questions/37771194