* which is not the case for the {@code java.util} equivalent.
   */
  public abstract T or(T defaultValue);

  /**
   * Returns this {@code Optional} if it has a value present; {@code secondChoice} otherwise.
   *
   * <p><b>Comparison to {@code java.util.Optional}:</b> this method has no equivalent in Java 8's

  }

  protected void initMapWithNullKey() {
    resetMap(createArrayWithNullKey());
  }

  protected void initMapWithNullValue() {
    resetMap(createArrayWithNullValue());
  }

  /**
   * Equivalent to {@link #expectMissingKeys(Object[]) expectMissingKeys} {@code (null)} except that
   * the call to {@code contains(null)} is permitted to throw a {@code NullPointerException}.
   *

   * traversing {@code node}'s incoming edges <i>against</i> the direction (if any) of the edge.
   *
   * <p>In an undirected graph, this is equivalent to {@link #adjacentNodes(Object)}.
   *
   * <p>If {@code node} is removed from the graph after this method is called, the `Set` returned by

          if (e.getHash() == hash
              && entryKey != null
              && map.keyEquivalence.equivalent(key, entryKey)) {
            ValueReference<K, V> valueReference = e.getValueReference();
            V entryValue = valueReference.get();

            RemovalCause cause;
            if (map.valueEquivalence.equivalent(value, entryValue)) {
              cause = RemovalCause.EXPLICIT;

  /**
   * Not really a signature -- just the parts that affect whether one method is a fauxveride of a
   * method from an ancestor class.
   *
   * <p>See JLS 8.4.2 for the definition of the related "override-equivalent."
   */
  private static final class MethodSignature implements Comparable<MethodSignature> {
    final String name;
    final List<Class<?>> parameterTypes;
    final TypeSignature typeSignature;

  /**
   * Not really a signature -- just the parts that affect whether one method is a fauxveride of a
   * method from an ancestor class.
   *
   * <p>See JLS 8.4.2 for the definition of the related "override-equivalent."
   */
  private static final class MethodSignature implements Comparable<MethodSignature> {
    final String name;
    final List<Class<?>> parameterTypes;
    final TypeSignature typeSignature;

  private void readObject(ObjectInputStream stream) throws InvalidObjectException {
    throw new InvalidObjectException("Use SerializedForm");
  }

  /**
   * Returns a new builder. The generated builder is equivalent to the builder created by the {@link
   * Builder} constructor.
   */
  public static <E> Builder<E> builder() {
    return new Builder<>();
  }

  /**

   */
  public static int compare(float a, float b) {
    return Float.compare(a, b);
  }

  /**
   * Returns {@code true} if {@code value} represents a real number. This is equivalent to, but not
   * necessarily implemented as, {@code !(Float.isInfinite(value) || Float.isNaN(value))}.
   *
   * <p><b>Java 8+ users:</b> use {@link Float#isFinite(float)} instead.
   *
   * @since 10.0
   */

      dst[offset + i] = get(i);
    }
    return offset + size;
  }

  /**
   * Returns a view of this immutable list in reverse order. For example, {@code ImmutableList.of(1,
   * 2, 3).reverse()} is equivalent to {@code ImmutableList.of(3, 2, 1)}.
   *
   * @return a view of this immutable list in reverse order
   * @since 7.0
   */
  public ImmutableList<E> reverse() {

 */
@GwtCompatible(emulated = true)
@ElementTypesAreNonnullByDefault
public final class Utf8 {
  /**
   * Returns the number of bytes in the UTF-8-encoded form of {@code sequence}. For a string, this
   * method is equivalent to {@code string.getBytes(UTF_8).length}, but is more efficient in both
   * time and space.
   *
   * @throws IllegalArgumentException if {@code sequence} contains ill-formed UTF-16 (unpaired
   *     surrogates)
   */