/**
   * Returns the sum of all values in this map.
   *
   * <p>This method is not atomic: the sum may or may not include other concurrent operations.
   */
  public long sum() {
    return map.values().stream().mapToLong(Long::longValue).sum();
  }

  @LazyInit @CheckForNull private transient Map<K, Long> asMap;

  /** Returns a live, read-only view of the map backing this {@code AtomicLongMap}. */
  public Map<K, Long> asMap() {

            completedWorkers.clear();
        }

        private String format(ToLongFunction<CollectingWorkerStats> statsProperty) {
            BigDecimal averageNanos = BigDecimal.valueOf(completedWorkers.stream().mapToLong(statsProperty).sum() / completedWorkers.size());
            return DecimalFormat.getNumberInstance().format(averageNanos.divide(BigDecimal.valueOf(1000000), RoundingMode.HALF_UP)) + "ms";
        }
    }

 *   <li>Can be queried without allocating garbage.
 *   <li>Access to {@code LongStream} features (like {@link LongStream#sum}) using {@code stream()}
 *       instead of the awkward {@code stream().mapToLong(v -> v)}.
 * </ul>
 *
 * <p>Disadvantages compared to {@code ImmutableList<Long>}:
 *
 * <ul>
 *   <li>Can't be passed directly to methods that expect {@code Iterable}, {@code Collection}, or