}
        });
  }

  private long doMultithreadedLoop(Callable<Long> task)
      throws InterruptedException, ExecutionException {

    List<Future<Long>> futures = Lists.newArrayListWithCapacity(threads);
    for (int i = 0; i < threads; i++) {
      futures.add(threadPool.submit(task));
    }
    long total = 0;
    for (Future<Long> future : futures) {
      total += future.get();
    }

          }
        });
  }

  private long doMultithreadedLoop(Callable<Long> task)
      throws InterruptedException, ExecutionException {

    List<Future<Long>> futures = Lists.newArrayListWithCapacity(threads);
    for (int i = 0; i < threads; i++) {
      futures.add(threadPool.submit(task));
    }
    long total = 0;
    for (Future<Long> future : futures) {
      total += future.get();
    }