@Throws(IOException::class)
  override fun authenticate(
    route: Route?,
    response: Response,
  ): Request? {
    if (route == null) throw NullPointerException("route == null")
    responses += response
    routes += route
    if (!schemeMatches(response) || credential == null) return null
    val header =
      when (response.code) {
        407 -> "Proxy-Authorization"
        else -> "Authorization"
      }

     *
     * @param key the key under which to store the session data, must not be {@code null}
     * @param oldValue the expected data currently associated with the key, may be {@code null}
     * @param newValue the data to associate with the key, may be {@code null} to remove the mapping
     * @return {@code true} if the key mapping was successfully updated from the old value to the new value,

  public void testAddAtIndex_nullSupported() {
    getList().add(0, null);
    expectAdded(0, (E) null);
  }

  @ListFeature.Require(SUPPORTS_ADD_WITH_INDEX)
  @CollectionFeature.Require(absent = ALLOWS_NULL_VALUES)
  public void testAddAtIndex_nullUnsupported() {
    assertThrows(NullPointerException.class, () -> getList().add(0, null));
    expectUnchanged();

    String stateString = requestUrl.queryParameter("state");
    ByteString state = stateString != null ? ByteString.decodeBase64(stateString) : null;

    Listener listener;
    synchronized (this) {
      listener = listeners.get(state);
    }

    if (code == null || listener == null) {
      return new MockResponse()
          .setResponseCode(404)
          .setBody("unexpected request");
    }

   * comparably to {@link Collections#singletonList}, but will not accept a null element. It is
   * preferable mainly for consistency and maintainability of your code.
   *
   * @throws NullPointerException if the element is null
   */
  public static <E> ImmutableList<E> of(E e1) {
    return construct(e1);
  }

  /**

   *
   * <p>Example:
   *
   * <pre>{@code
   * Ordering.allEqual().nullsLast().sortedCopy(
   *     asList(t, null, e, s, null, t, null))
   * }</pre>
   *
   * <p>Assuming {@code t}, {@code e} and {@code s} are non-null, this returns {@code [t, e, s, t,
   * null, null, null]} regardless of the true comparison order of those three values (which might
   * not even implement {@link Comparable} at all).
   *

      @CheckForNull @Nullable ImmutableMapEntry<?, V>[] keyTable,
      int mask) {
    if (key == null || keyTable == null) {
      return null;
    }
    int index = Hashing.smear(key.hashCode()) & mask;
    for (ImmutableMapEntry<?, V> entry = keyTable[index];
        entry != null;
        entry = entry.getNextInKeyBucket()) {
      Object candidateKey = entry.getKey();

      /*

        final Pair<T1, T2> other = (Pair<T1, T2>) obj;
        if (first == null) {
            if (other.first != null) {
                return false;
            }
        } else if (!first.equals(other.first)) {
            return false;
        }
        if (second == null) {
            if (other.second != null) {
                return false;
            }

    @After
    public void tearDown () throws Exception {
        if ( this.executor != null ) {
            this.executor.shutdown();
            if ( this.future != null ) {
                this.future.cancel(true);
            }
            this.executor.awaitTermination(1, TimeUnit.SECONDS);
        }
        if ( this.base != null ) {
            this.base.delete();
        }
        super.tearDown();
    }

    assertThat(expected).hasMessageThat().isEqualTo("null");
  }

  public void testCheckArgument_nullMessageWithArgs_failure() {
    IllegalArgumentException e =
        assertThrows(IllegalArgumentException.class, () -> checkArgument(false, null, "b", "d"));
    assertThat(e).hasMessageThat().isEqualTo("null [b, d]");
  }