EJB @Schedule wait until method completed

Question

I want to write a back-ground job (EJB 3.1), which executes every minute. For this I use the following annotation:

@Schedule(minute = \"*/1\", hour = \"*\")
         


        

Answer 1

Since Java EE 7 it is possible to use an "EE-aware" ManagedScheduledExecutorService, i.e. in WildFly:

In for example a @Singleton @Startup @LocalBean, inject the default "managed-scheduled-executor-service" configured in standalone.xml:

@Resource
private ManagedScheduledExecutorService scheduledExecutorService;

Schedule some task in @PostConstruct to be executed i.e. every second with fixed delay:

scheduledExecutorService.scheduleWithFixedDelay(this::someMethod, 1, 1, TimeUnit.SECONDS);

scheduleWithFixedDelay:

Creates and executes a periodic action that becomes enabled first after the given initial delay, and subsequently with the given delay between the termination of one execution and the commencement of the next.[...]

Do not shutdown the scheduler in i.e. @PreDestroy:

Managed Scheduled Executor Service instances are managed by the application server, thus Java EE applications are forbidden to invoke any lifecycle related method.