* order.
   */
  @Override
  // TODO(kevinb): caveats about equivalence-relation?
  boolean equals(@Nullable Object object);

  /**
   * Returns the hash code for this multiset. This is defined as the sum of
   *
   * {@snippet :
   * ((element == null) ? 0 : element.hashCode()) ^ count(element)
   * }
   *
   * <p>over all distinct elements in the multiset. It follows that a multiset and its entry set

      b += minDeltaOrZero; // sets b to min(old a, b)
      a >>= Long.numberOfTrailingZeros(a); // divide out all 2s, since 2 doesn't divide b
    }
    return a << min(aTwos, bTwos);
  }

  /**
   * Returns the sum of {@code a} and {@code b}, provided it does not overflow.
   *
   * <p><b>Note:</b> this method is now unnecessary and should be treated as deprecated; use {@link

  }

  public void testSum() {
    assertThat(emptyAccumulator.sum()).isEqualTo(0.0);
    assertThat(emptyAccumulatorByAddAllEmptyIterable.sum()).isEqualTo(0.0);
    assertThat(emptyAccumulatorByAddAllEmptyStats.sum()).isEqualTo(0.0);
    assertThat(oneValueAccumulator.sum()).isWithin(ALLOWED_ERROR).of(ONE_VALUE);
    assertThat(oneValueAccumulatorByAddAllEmptyStats.sum()).isWithin(ALLOWED_ERROR).of(ONE_VALUE);

		unsealConfig = sio.Config{MinVersion: sio.Version20, Key: mac.Sum(nil)}
	case InsecureSealAlgorithm:
		sha := sha256.New()
		sha.Write(extKey)
		sha.Write(sealedKey.IV[:])
		unsealConfig = sio.Config{MinVersion: sio.Version10, Key: sha.Sum(nil)}
	}

	if out, err := sio.DecryptBuffer(key[:0], sealedKey.Key[:], unsealConfig); len(out) != 32 || err != nil {

		totalDrives := onlineDrives.Merge(offlineDrives)

		v = storageMetrics{
			storageInfo:   storageInfo,
			onlineDrives:  onlineDrives.Sum(),
			offlineDrives: offlineDrives.Sum(),
			totalDrives:   totalDrives.Sum(),
			ioStats:       map[string]driveIOStatMetrics{},
		}

		currentStats := getCurrentDriveIOStats()
		now := time.Now().UTC()

		prevDriveIOStatsMu.Lock()

  }

  public void testSum() {
    assertThat(emptyAccumulator.sum()).isEqualTo(0.0);
    assertThat(emptyAccumulatorByAddAllEmptyIterable.sum()).isEqualTo(0.0);
    assertThat(emptyAccumulatorByAddAllEmptyStats.sum()).isEqualTo(0.0);
    assertThat(oneValueAccumulator.sum()).isWithin(ALLOWED_ERROR).of(ONE_VALUE);
    assertThat(oneValueAccumulatorByAddAllEmptyStats.sum()).isWithin(ALLOWED_ERROR).of(ONE_VALUE);

      return new CacheStats(
          negativeToMaxValue(hitCount.sum()),
          negativeToMaxValue(missCount.sum()),
          negativeToMaxValue(loadSuccessCount.sum()),
          negativeToMaxValue(loadExceptionCount.sum()),
          negativeToMaxValue(totalLoadTime.sum()),
          negativeToMaxValue(evictionCount.sum()));
    }

	}
	buf, err = madmin.EncryptData(secretKey, buf)
	if err != nil {
		c.Fatalf("unexpected encryption err: %v", err)
	}

	req.ContentLength = int64(len(buf))
	sum := sha256.Sum256(buf)
	req.Header.Set("X-Amz-Content-Sha256", hex.EncodeToString(sum[:]))
	req.Body = io.NopCloser(bytes.NewReader(buf))
	req = signer.SignV4(*req, accessKey, secretKey, "", "")

	// 3.1 Execute the request.

  public void testOverflows() {
    LongAdder longAdder = new LongAdder();
    longAdder.add(Long.MAX_VALUE);
    assertThat(longAdder.sum()).isEqualTo(Long.MAX_VALUE);
    longAdder.add(1);
    // silently overflows; is this a bug?
    // See https://github.com/google/guava/issues/3503
    assertThat(longAdder.sum()).isEqualTo(-9223372036854775808L);
  }

      return new CacheStats(
          negativeToMaxValue(hitCount.sum()),
          negativeToMaxValue(missCount.sum()),
          negativeToMaxValue(loadSuccessCount.sum()),
          negativeToMaxValue(loadExceptionCount.sum()),
          negativeToMaxValue(totalLoadTime.sum()),
          negativeToMaxValue(evictionCount.sum()));
    }