code: @Override
    public void workerPreempted(final String id) {
      final Optional<Collection<Tasklet>> preemptedTasklets = runningWorkers.removeWorker(id);
      if (preemptedTasklets.isPresent()) {
        for (final Tasklet tasklet : preemptedTasklets.get()) {
          pendingTasklets.addFirst(tasklet);
        }
      }
    }
docs: Remove the worker from runningWorkers and add back the lost tasklets to pendingTasklets.