Delete expired data in table (Kotlin)

Question

I have a table in Spring application, that I need to delete expired info after a certain period of time in background. There is a code:

@Service
class HistoryService constructor(
private val historyRepository: HistoryRepository,  {
    companion object {
        fun deleteHistory() {
            historyRepository.deleteAll()
        }

Starter class

@SpringBootApplication
@EnableScheduling
class Starter {

  fun main(args: Array<String>) {
    TimeZone.setDefault(TimeZone.getTimeZone("UTC"))
    runApplication<Starter>(*args)
    val taskService = TaskService
    val ses = Executors.newScheduledThreadPool(10)
    ses.scheduleAtFixedRate({
       taskService.transferTask()
    }, 0, 10000, TimeUnit.SECONDS)
  }
}

I am not sure that is this a corect way, because in this case there is no transaction annotation in method and in debug I noticed that the application execute this method only one time. How should I change the code to have a service method that will work with database in background?

Answer 1

Your function shouldn't be called main (it's confusing as it looks like the top level main method, but it's within a class which is a Java way of defining main, not a Kotlin way), nor should it have parameters as it's not called from anything other than Spring's scheduling code.

So just have a function inside your configuration class, and annotate it with @Scheduled e.g.

@SpringBootApplication
@EnableScheduling
class Starter  {

   @Scheduled(fixedDelay = 1000){
   fun doIt() {
       taskService.transferTask()
   }
}