Parelelizing Void Method in Java using google Thread Factory

Snippet.java

ThreadFactory factory = com.google.appengine.api.ThreadManager.currentRequestThreadFactory();
ExecutorService service = new ThreadPoolExecutor(Runtime.getRuntime().availableProcessors(), 16, 60, TimeUnit.SECONDS, new SynchronousQueue<>(), factory);
List<Future<Void>> futures = new ArrayList<>();

for (String tempStopAccountId : aristoDto.getTempStopHdAccountIds()) {
    if (aristoDto.getProductFileDtoMap().get(tempStopAccountId) != null) {
        aristoDto.getProductFileDtoMap().get(tempStopAccountId).setTempAccount(true);
    }
   Callable<Void> callable = () -> {
    futures.add(processCancellation(tempStopAccountId));
       return null;
   };
   futures.add(service.submit(callable));
}

service.shutdown();
log.info("Waiting for temp calls to come back");

for (Future<Void> future : futures){
    try {
        future.get();
    } catch (InterruptedException e) {
        e.printStackTrace();
    } catch (ExecutionException e) {
        e.printStackTrace();
    } catch (Exception e) {
        e.printStackTrace();
    }
}