Question

I have a ScheduledThreadPoolExecutor that seems to be eating Exceptions. I want my executor service to notify me if a submitted Runnable throws an exception.

For example, I’d like the code below to at the very least print the IndexArrayOutOfBoundsException’s stackTrace

threadPool.scheduleAtFixedRate(
  new Runnable() {
    public void run() {
      int[] array = new array[0];
      array[42] = 5;
    }
  },
  1000,
  1500L,
  TimeUnit.MILLISECONDS);

As a side question. Is there a way to write a general try catch block for a ScheduledThreadPoolExecutor?

//////////END OF ORIGINAL QUESTION //////////////

As suggested the following Decorator works well.

public class CatcherTask implements Runnable{

    Runnable runMe;

    public CatcherTask(Runnable runMe) {
        this.runMe = runMe;
    }

    public void run() {
        try {
            runMe.run();
        } catch (Exception ex){
            ex.printStackTrace();
        }
    }
}

Answer 1

I wrote a small post about this problem a while ago. You have two options:

1. Use the solution provided by Colin Herbert or
2. use a modified version of Mark Peters solution but instead of assigning a UncaughtExceptionHandler you wrap each submitted runnable into a runnable of your own which executes (calls run) the real runnable inside a try-catch-block.

EDIT
As pointed out by Mark, it’s important to wrap the Runnable passed to ScheduledExecutorService instead of the one passed to the ThreadFactory.