* {@link java.util.concurrent.CompletableFuture#thenComposeAsync}. It can also serve some of the
   * use cases of {@link java.util.concurrent.CompletableFuture#handle} and {@link
   * java.util.concurrent.CompletableFuture#handleAsync} when used along with {@link #catching}.
   *
   * @param function A function to transform the result of this future to the result of the output
   *     future
   * @param executor Executor to run the function in.

    return new RegularImmutableBiMap<K, V>(ImmutableMap.of(k1, v1, k2, v2, k3, v3));
  }

  public static <K, V> ImmutableBiMap<K, V> of(K k1, V v1, K k2, V v2, K k3, V v3, K k4, V v4) {
    return new RegularImmutableBiMap<K, V>(ImmutableMap.of(k1, v1, k2, v2, k3, v3, k4, v4));
  }

  public static <K, V> ImmutableBiMap<K, V> of(

    Collection<String> c = of("a", "b", "c");
    assertFalse(c.containsAll(of("a", "b", "c", "d")));
    assertFalse(c.containsAll(of("a", "d")));
    assertTrue(c.containsAll(of("a", "c")));
    assertTrue(c.containsAll(of("a", "b", "c")));
  }

  public void testEquals_sameType() {
    Collection<String> c = of("a", "b", "c");
    assertTrue(c.equals(of("a", "b", "c")));

    Collection<String> c = of("a", "b", "c");
    assertFalse(c.containsAll(of("a", "b", "c", "d")));
    assertFalse(c.containsAll(of("a", "d")));
    assertTrue(c.containsAll(of("a", "c")));
    assertTrue(c.containsAll(of("a", "b", "c")));
  }

  public void testEquals_sameType() {
    Collection<String> c = of("a", "b", "c");
    assertTrue(c.equals(of("a", "b", "c")));

   * Constructs an {@code ImmutableSortedSet} from the first {@code n} elements of {@code contents}.
   * If {@code k} is the size of the returned {@code ImmutableSortedSet}, then the sorted unique
   * elements are in the first {@code k} positions of {@code contents}, and {@code contents[i] ==
   * null} for {@code k <= i < n}.
   *
   * <p>This method takes ownership of {@code contents}; do not modify {@code contents} after this
   * returns.
   *

 *       with the same key. Some behaviors of {@link Multimap} are left unspecified and are provided
 *       only by the subtypes mentioned below.
 *   <dt>{@link ListMultimap}
 *   <dd>An extension of {@link Multimap} which permits duplicate entries, supports random access of
 *       values for a particular key, and has <i>partially order-dependent equality</i> as defined

  }

  /**
   * Returns a string containing the string representation of each of {@code parts}, using the
   * previously configured separator between each.
   */
  public final String join(Iterable<? extends @Nullable Object> parts) {
    return join(parts.iterator());
  }

  /**
   * Returns a string containing the string representation of each of {@code parts}, using the
   * previously configured separator between each.

 *
 * <p>The average time complexity of the computation is O(N) in the size of the dataset. There is a
 * worst case time complexity of O(N^2). You are extremely unlikely to hit this quadratic case on
 * randomly ordered data (the probability decreases faster than exponentially in N), but if you are
 * passing in unsanitized user data then a malicious user could force it. A light shuffle of the

  // TODO(kevinb): evaluate whether or not of().comparator() should return null
  public static <K, V> ImmutableSortedMap<K, V> of() {
    return (ImmutableSortedMap<K, V>) NATURAL_EMPTY_MAP;
  }

  /** Returns an immutable map containing a single entry. */
  public static <K extends Comparable<? super K>, V> ImmutableSortedMap<K, V> of(K k1, V v1) {
    return of(Ordering.natural(), k1, v1);
  }

 * override one or more methods to modify the behavior of the backing sorted set as desired per the
 * <a href="http://en.wikipedia.org/wiki/Decorator_pattern">decorator pattern</a>.
 *
 * <p><b>Warning:</b> The methods of {@code ForwardingSortedSet} forward <i>indiscriminately</i> to
 * the methods of the delegate. For example, overriding {@link #add} alone <i>will not</i> change