*       }
 *     };
 * iteratorTester.test();
 * iteratorTester.testForEachRemaining();
 * }</pre>
 *
 * <p><b>Note</b>: It is necessary to use {@code IteratorTester.KnownOrder} as shown above, rather
 * than {@code KnownOrder} directly, because otherwise the code cannot be compiled.
 *
 * @author Kevin Bourrillion
 * @author Chris Povirk
 */
@GwtCompatible
@ElementTypesAreNonnullByDefault

     * into {@code horizon} between calls to {@code visitNext()}. This causes them to receive
     * additional values interleaved with those shown above.)
     */
    @CheckForNull
    abstract N visitNext(Deque<Iterator<? extends N>> horizon);
  }

  /** Poor man's method reference for {@code Deque::addFirst} and {@code Deque::addLast}. */

 * later RFCs with the apparent aim of making IPv4-to-IPv6 transition simpler.
 *
 * <p>Technically one <i>can</i> create a 128bit IPv6 address with the wire format of a "mapped"
 * address, as shown above, and transmit it in an IPv6 packet header. However, Java's InetAddress
 * creation methods appear to adhere doggedly to the original intent of the "mapped" address: all
 * "mapped" addresses return {@link Inet4Address} objects.

 * </ul>
 *
 * <p><b>Important:</b> although the first interpretation resembles how most multimaps are
 * <i>implemented</i>, the design of the {@code Multimap} API is based on the <i>second</i> form.
 * So, using the multimap shown above as an example, the {@link #size} is {@code 3}, not {@code 2},
 * and the {@link #values} collection is {@code [1, 2, 3]}, not {@code [[1, 2], [3]]}. For those

 *       }
 *     };
 * iteratorTester.test();
 * iteratorTester.testForEachRemaining();
 * }</pre>
 *
 * <p><b>Note</b>: It is necessary to use {@code IteratorTester.KnownOrder} as shown above, rather
 * than {@code KnownOrder} directly, because otherwise the code cannot be compiled.
 *
 * @author Kevin Bourrillion
 * @author Chris Povirk
 */
@GwtCompatible
@ElementTypesAreNonnullByDefault

   *
   * @since 20.0
   */
  public static final String FORWARDED = "Forwarded";
  /**
   * The HTTP {@code Follow-Only-When-Prerender-Shown} header field name.
   *
   * @since 17.0
   */
  public static final String FOLLOW_ONLY_WHEN_PRERENDER_SHOWN = "Follow-Only-When-Prerender-Shown";
  /** The HTTP {@code Host} header field name. */
  public static final String HOST = "Host";
  /**