int sum = 0;
    for (int i = 0; i < reps; i++) {
      for (Object value : arrayList) {
        sum += value.hashCode();
      }
    }
    return sum;
  }

  @Benchmark
  int arrayListForWithHolder(int reps) {
    int[] sumHolder = {0};
    for (int i = 0; i < reps; i++) {
      for (Object value : arrayList) {
        sumHolder[0] += value.hashCode();
      }
    }
    return sumHolder[0];