Time limit on individual threads with ExecutorService

Question

I have an ExecutorService managing a number of Callables. The tasks that the Callables run are mostly black box transformations and number crunching. Under certain condition

Answer 1

Use a ScheduleExecutorService to schedule a task to taskFuture.cancel(true) the long running task when the timeout is reached. If the task finishes before then it won't be cancelled.

ExecutorService service = Executors.newFixedThreadPool(N);
ScheduledExecutorService canceller = Executors.newSingleThreadScheduledExecutor();

public  Future executeTask(Callable c, long timeoutMS){
   final Future future = service.submit(c);
   canceller.schedule(new Callable(){
       public Void call(){
          future.cancel(true);
          return null;
       }
    }, timeoutMS, TimeUnit.MILLI_SECONDS);
   return future;
}