How do i get ScheduledExecutorService to keep executing other subsequent tasks when one task throws an exception

Question

I have got an executor that executes a task every 5 sec

public class ScheduledTaskExecutor {

  public int execute(){
    ScheduledExecutorService executor = Executors.newScheduledThreadPool(4);
    executor.scheduleAtFixedRate(new Task().run,3,5, TimeUnit.SECONDS);
    return -1;
  }

}

Here's the task. I'm throwing an IllegalArgumentException if X == 4

public class Task {

    private static final Logger LOG = LoggerFactory.getLogger(DcEmailTask.class);
    private int x = 0;


    public Runnable run = () -> {
        String currentThread = Thread.currentThread().getName();
        x++;
        System.out.println("Thread [" + currentThread + "] is executing the task: " + x);
        if (x == 4) throw new IllegalArgumentException();
    };

}

The program stops executing and no stack trace is printed.

I was just wondering what you wanted to do, afte read your post I did not found out, because in the title there is no question and you talk about "subsequent task" And i did not get it after reading, so don't be rude ;) — azro, Jan 26 '19 at 10:26

score 0 · Answer 1 · answered Jan 26 '19 at 10:11

0

This behavior is as per the javadoc of ScheduledExecutorService#scheduleAtFixedRate. One way to solve the issue is to catch all the exceptions in runnable.

This answer has more details https://stackoverflow.com/a/24902026/3002471

answered Jan 26 '19 at 10:11

Sairam Cherupally

341
3
12

so true but one may think only the executing thread should be terminated and not all threads in the pool. Anyways..thanks. – theyCallMeJun Jan 26 '19 at 10:24

score 0 · Answer 2 · answered Jan 26 '19 at 11:02

Implement ScheduledExecutorService interface (SESWrrapper) that accepts another ScheduledExecutorService in its constructor.
Implement Runnable interface (SafeRunnableWrapper) that accepts another Runnable in its constructor and capture exceptions inside of its run() method.
Implement Callable interface (SafeCallableWrapper) as above.
In SESWrrapper.(Runnable, long, TimeUnit) methods wrap Runnable with SafeRunnableWrapper and invoke nested ScheduledExecutorService.schedule().

How do i get ScheduledExecutorService to keep executing other subsequent tasks when one task throws an exception

2 Answers2