override fun close() {
    close(ErrorCode.NO_ERROR, ErrorCode.CANCEL, null)
  }

  internal fun close(
    connectionCode: ErrorCode,
    streamCode: ErrorCode,
    cause: IOException?,
  ) {
    assertLockNotHeld()

    ignoreIoExceptions {
      shutdown(connectionCode)
    }

    var streamsToClose: Array<Http2Stream>? = null
    withLock {
      if (streams.isNotEmpty()) {

     *
     * @return The model being built, never {@code null}.
     */
    Model getModel();

    /**
     * Gets the model building request being processed.
     *
     * @return The model building request being processed, never {@code null}.
     */
    ModelBuildingRequest getRequest();

    /**

        oldMethods.removeAll(newMethods)

        if (oldMethods.isEmpty()) {
            return null
        }

        List<String> changes = filterChangesToReport(oldClass, oldMethods)
        if (changes.isEmpty()) {
            return null
        }
        return acceptOrReject(c, changes, Violation.error(c, " methods removed in internal super class"))
    }

  public void testEquals_otherListContainingNull() {
    List<E> other = new ArrayList<>(getSampleElements());
    other.set(other.size() / 2, null);
    assertFalse(
        "Two Lists should not be equal if exactly one of them has null at a given index.",
        getList().equals(other));
  }

  @CollectionSize.Require(absent = CollectionSize.ZERO)
  @CollectionFeature.Require(ALLOWS_NULL_VALUES)

  public void testCount_nullAbsent() {
    assertEquals("multiset.count(null) didn't return 0", 0, getMultiset().count(null));
  }

  @CollectionFeature.Require(absent = ALLOWS_NULL_QUERIES)
  public void testCount_null_forbidden() {
    assertThrows(NullPointerException.class, () -> getMultiset().count(null));
  }

  @CollectionSize.Require(absent = ZERO)
  @CollectionFeature.Require(ALLOWS_NULL_VALUES)

 *       typically because the type forbids nullable type arguments: For example, {@code
 *       ImmutableList.get} returns {@code E}, but that value is never {@code null}. (Accordingly,
 *       {@code ImmutableList} is declared to forbid {@code ImmutableList<@Nullable String>}.)
 *   <li>methods whose return type is a type variable but which can return {@code null} regardless

 *       typically because the type forbids nullable type arguments: For example, {@code
 *       ImmutableList.get} returns {@code E}, but that value is never {@code null}. (Accordingly,
 *       {@code ImmutableList} is declared to forbid {@code ImmutableList<@Nullable String>}.)
 *   <li>methods whose return type is a type variable but which can return {@code null} regardless

        public void mergeManagedBuildPlugins(Model model) {
            Build build = model.getBuild();
            if (build != null) {
                PluginManagement pluginManagement = build.getPluginManagement();
                if (pluginManagement != null) {
                    mergePluginContainerPlugins(build, pluginManagement);
                }
            }
        }

  /**
   * A word about using {@link Equivalence}, which automatically checks for {@code null} and
   * identical inputs: This sounds like it ought to be a problem here, since the goals of this class
   * include testing that {@code equals()} is reflexive and is tolerant of {@code null}. However,
   * there's no problem. The reason: {@link EqualsTester} tests {@code null} and identical inputs

        }
      }.build()

  class Builder {
    internal var client: OkHttpClient? = null
    internal var url: HttpUrl? = null
    internal var includeIPv6 = true
    internal var post = false
    internal var systemDns = Dns.SYSTEM
    internal var bootstrapDnsHosts: List<InetAddress>? = null
    internal var resolvePrivateAddresses = false
    internal var resolvePublicAddresses = true