/* nothing */
  }

  /**
   * This Iterator claims to have more elements than the underlying iterable, but when you try to
   * fetch the extra elements, it throws an unchecked exception.
   */
  static class ThrowsAtEndIterator<E> implements Iterator<E> {
    Iterator<E> iterator;

    public ThrowsAtEndIterator(Iterable<E> iterable) {
      this.iterator = iterable.iterator();

    checkNotNull(mergeFunction);
    return Collectors.collectingAndThen(
        Collectors.toMap(keyFunction, valueFunction, mergeFunction, LinkedHashMap::new),
        ImmutableMap::copyOf);
  }

  @SuppressWarnings("unchecked") // An empty map works for all types.
  public static <K, V> ImmutableMap<K, V> of() {
    return (ImmutableMap<K, V>) RegularImmutableMap.EMPTY;
  }

  public static <K, V> ImmutableMap<K, V> of(K k1, V v1) {

   * consistency, and because the return type conveys the immutability guarantee.
   *
   * <p><b>Performance note:</b> the instance returned is a singleton.
   */
  @SuppressWarnings({"unchecked"}) // fully variant implementation (never actually produces any Es)
  public static <E> ImmutableSet<E> of() {
    return (ImmutableSet<E>) RegularImmutableSet.EMPTY;
  }

  /**

    return Lists.newArrayList(iterable);
  }

  @Override
  public <E> ImmutableList<E> immutableSortedCopy(Iterable<E> iterable) {
    return ImmutableList.copyOf(iterable);
  }

  @SuppressWarnings("unchecked")
  @Override
  public <S extends @Nullable Object> Ordering<S> reverse() {
    return (Ordering<S>) this;
  }

  private Object readResolve() {
    return INSTANCE;
  }

  @Override

    return Lists.newArrayList(iterable);
  }

  @Override
  public <E> ImmutableList<E> immutableSortedCopy(Iterable<E> iterable) {
    return ImmutableList.copyOf(iterable);
  }

  @SuppressWarnings("unchecked")
  @Override
  public <S extends @Nullable Object> Ordering<S> reverse() {
    return (Ordering<S>) this;
  }

  private Object readResolve() {
    return INSTANCE;
  }

  @Override

    return CollectCollectors.toImmutableBiMap(keyFunction, valueFunction);
  }

  // Casting to any type is safe because the set will never hold any elements.
  @SuppressWarnings("unchecked")
  public static <K, V> ImmutableBiMap<K, V> of() {
    return (ImmutableBiMap<K, V>) RegularImmutableBiMap.EMPTY;
  }

  public static <K, V> ImmutableBiMap<K, V> of(K k1, V v1) {
    checkEntryNotNull(k1, v1);

   * false} for {@code boolean} and {@code '\0'} for {@code char}. For non-primitive types and
   * {@code void}, {@code null} is returned.
   */
  @SuppressWarnings({
    "unchecked",
    "BooleanLiteral" // `(T) false` would produce an error
  })
  public static <T> @Nullable T defaultValue(Class<T> type) {
    checkNotNull(type);
    if (type.isPrimitive()) {
      if (type == boolean.class) {

   *
   * <p><b>Discouraged:</b> Prefer using a lambda like {@code v -> v}, which is shorter and often
   * more readable.
   */
  // implementation is "fully variant"; E has become a "pass-through" type
  @SuppressWarnings("unchecked")
  public static <E extends @Nullable Object> Function<E, E> identity() {
    return (Function<E, E>) IdentityFunction.INSTANCE;
  }

  // enum singleton pattern

    List<Class<?>> interfaces = new ArrayList<>(Arrays.asList(forwarderClass.getInterfaces()));
    // Desugaring may introduce AutoCloseable as an extra interface.
    interfaces.remove(AutoCloseable.class);
    @SuppressWarnings("unchecked") // super interface type of T
    Class<? super T> interfaceType = (Class<? super T>) Iterables.getOnlyElement(interfaces);
    new ForwardingWrapperTester()
        .testForwarding(
            interfaceType,

    List<Class<?>> interfaces = new ArrayList<>(Arrays.asList(forwarderClass.getInterfaces()));
    // Desugaring may introduce AutoCloseable as an extra interface.
    interfaces.remove(AutoCloseable.class);
    @SuppressWarnings("unchecked") // super interface type of T
    Class<? super T> interfaceType = (Class<? super T>) Iterables.getOnlyElement(interfaces);
    new ForwardingWrapperTester()
        .testForwarding(
            interfaceType,