case ADD:
            {
              int delta = random.nextInt(10);
              multiset.add(key, delta);
              deltas[keyIndex] += delta;
              break;
            }
          case SET_COUNT:
            {
              int newValue = random.nextInt(3);
              int oldValue = multiset.setCount(key, newValue);
              deltas[keyIndex] += newValue - oldValue;
              break;

          int key2 = key1 ^ delta;

          // get hashes
          int hash1 = function.hashInt(key1).asInt();
          int hash2 = function.hashInt(key2).asInt();

          // this 2-bit candidate delta is not a characteristic
          // if deltas are different
          if ((hash1 ^ hash2) != delta) {
            diff = true;
            continue;
          }

                        break;
                      case 5:
                        map.getAndAdd(key, delta);
                        threadSum += delta;
                        break;
                      case 6:
                        long oldValue = map.put(key, delta);
                        threadSum += delta - oldValue;
                        break;
                      case 7:

            Long.MIN_VALUE,
            Long.MAX_VALUE)) {
      for (double delta : Doubles.asList(0.0, 1.0, 2.0)) {
        integralBuilder.addAll(Doubles.asList(d + delta, d - delta, -d - delta, -d + delta));
      }
      for (double delta : Doubles.asList(0.01, 0.1, 0.25, 0.499, 0.5, 0.501, 0.7, 0.8)) {
        double x = d + delta;
        if (x != Math.round(x)) {
          fractionalBuilder.add(x);
        }
      }

  public long decrementAndGet(K key) {
    return addAndGet(key, -1);
  }

  /**
   * Adds {@code delta} to the value currently associated with {@code key}, and returns the new
   * value.
   */
  @CanIgnoreReturnValue
  public long addAndGet(K key, long delta) {
    return accumulateAndGet(key, delta, Long::sum);
  }

  /**

  }

  /**
   * @param delta the offset from the current date to use. Negative values yield dates in the past;
   *     positive values yield dates in the future.
   */
  private fun formatDate(
    delta: Long,
    timeUnit: TimeUnit,
  ): String? = formatDate(Date(System.currentTimeMillis() + timeUnit.toMillis(delta)))

  private fun formatDate(date: Date): String? {

    final List<E> delegate;
    final int delta;

    MisleadingSizeList(List<E> delegate, int delta) {
      this.delegate = delegate;
      this.delta = delta;
    }

    @Override
    protected List<E> delegate() {
      return delegate;
    }

    @Override
    public int size() {
      return delegate.size() + delta;
    }
  }

    }
  }

  companion object {
    internal const val EMIT_BUFFER_SIZE = 16384L
  }

  /** [delta] will be negative if a settings frame initial window is smaller than the last. */
  fun addBytesToWriteWindow(delta: Long) {
    writeBytesMaximum += delta
    if (delta > 0L) {
      notifyAll()
    }
  }

  @Throws(IOException::class)
  internal fun checkOutNotClosed() {
    when {

   * size() as a hint only.
   *
   * @param delta the difference between the true size of the collection and the values returned by
   *     the size method
   */
  public static <T extends @Nullable Object> Collection<T> misleadingSizeCollection(int delta) {
    // It would be nice to be able to return a real concurrent

  /** The Greek letter delta, used in unicode testing. */
  private static final String DELTA = "\u0394";

  /** A domain part which is valid under lenient validation, but invalid under strict validation. */
  @SuppressWarnings("InlineMeInliner") // String.repeat unavailable under Java 8
  static final String LOTS_OF_DELTAS = Strings.repeat(DELTA, 62);