Spring : Schedule a task which takes a parameter

Question

I have a class with the following function:

public class classA{

... 
...

void function_to_be_scheduled(String param){
    ...
    ...
}
}

I want to schedule the function using the scheduled-tasks element of the task namespace.

<task:scheduled-tasks>
    <task:scheduled ref="beanA" method="function_to_be_scheduled" cron="${cron}"/>
</task:scheduled-tasks>

How do i pass the parameter to the function which i want to schedule?

Sideling

Answer 1

According to the docs you cant.

Notice that the methods to be scheduled must have void returns and must not expect any arguments.

Outdoors

Answer 2

The Spring doc about scheduling says:

Notice that the methods to be scheduled must have void returns and must not expect any arguments

Since the parameter comes from the Spring config file you can declare a bean (es beanB which wraps beanA) in the spring file, inject the parameter you need in the bean and the schedule the execution of a method of the bean which knows the parameter (it could be a simple wrapper of your beanA)

Vertigo

Answer 3

You can use TaskScheduler and encapsule your logic with a parameter in Runnable:

@Autowired
private TaskScheduler scheduler;

public void scheduleRules() {
    MyTask task = new MyTaskImpl(someParam);
    // new CronTrigger
    scheduler.scheduleAtFixedRate(task, Duration.ofMinutes(1));
}

Sassoon

Answer 4

I've found that the only way to do this is to have a façade method that is @Scheduled and knows the default value required. The useful side-effect of this is that you can also provide an API through a @Controller to provide manual triggering with a specific parameter - useful if you need to re-run an activity.

@Scheduled(cron = "${myChronSchedule}")
public void generateActivities() {

    this.generateActivities(LocalDate.now());

}

public void generateActivities(LocalDate theDate) {
    // do the work
    ...
}

If you don't need the façade to be public, there's no reason why it can't be private and no-one is the wiser.

Whencesoever

Answer 5

The Task Scheduler did the trick for me

1. First create a configuration class called ThreadPoolTaskScheduler class. Find details Here!

2. Then create a class where the magic happens

   @Component
   public class ThreadPoolTaskSchedulerExample {
   
   @Autowired
   private ThreadPoolTaskScheduler taskScheduler;
   
   
        class EmailWatch implements Runnable{
   
            private String userEmail;
   
   
            public EmailWatch(String userEmail){
                this.userEmail = userEmail;
            }
   
   
            @Override
            public void run() {
                 System.out.println("This is the email "+ userEmail);
            }
        }
   
   
        public void watchEmail(String userEmail)  {
   
      //refresh watch every minute
            CronTrigger cronTrigger = new CronTrigger("0 * * ? * *"); 
            taskScheduler.schedule(new EmailWatch(userEmail));
        }
    }
   

Frechette