*   if (value < 0) {
 *     throw new IllegalArgumentException("input is negative: " + value);
 *   }
 *   // calculate square root
 * }
 * }</pre>
 *
 * <p>to be replaced with the more compact
 *
 * <pre>{@code
 * public static double sqrt(double value) {
 *   checkArgument(value >= 0, "input is negative: %s", value);
 *   // calculate square root
 * }
 * }</pre>
 *

   *
   * <p>The recommended solution for finding the {@code minimum} of some values depends on the type
   * of your data and the number of elements you have. Read more in the Guava User Guide article on
   * <a href="https://github.com/google/guava/wiki/CollectionUtilitiesExplained#comparators">{@code
   * Comparators}</a>.
   *

tried hedges,' the Pigeon went on, without attending to her; `but
those serpents!  There's no pleasing them!'

  Alice was more and more puzzled, but she thought there was no
use in saying anything more till the Pigeon had finished.

  `As if it wasn't trouble enough hatching the eggs,' said the
Pigeon; `but I must be on the look-out for serpents night and

        "Shouldn't catch any more events when unregistered.", expectedEvents, catcher1.getEvents());
    assertEquals("Two correct events should be delivered.", expectedEvents, catcher2.getEvents());

    assertThrows(IllegalArgumentException.class, () -> bus.unregister(catcher1));

    bus.unregister(catcher2);
    bus.post(EVENT);
    assertEquals(

        "Shouldn't catch any more events when unregistered.", expectedEvents, catcher1.getEvents());
    assertEquals("Two correct events should be delivered.", expectedEvents, catcher2.getEvents());

    assertThrows(IllegalArgumentException.class, () -> bus.unregister(catcher1));

    bus.unregister(catcher2);
    bus.post(EVENT);
    assertEquals(

   *       the same.
   *   <li>The special characters ".", "-", "*", and "_" remain the same.
   *   <li>The space character " " is converted into a plus sign "+".
   *   <li>All other characters are converted into one or more bytes using UTF-8 encoding and each
   *       byte is then represented by the 3-character string "%XY", where "XY" is the two-digit,
   *       uppercase, hexadecimal representation of the byte value.
   * </ul>
   *

    /**
     * Returns a new immutable array. The builder can continue to be used after this call, to append
     * more values and build again.
     *
     * <p><b>Performance note:</b> the returned array is backed by the same array as the builder, so
     * no data is copied as part of this step, but this may occupy more memory than strictly
     * necessary. To copy the data to a right-sized backing array, use {@code .build().trimmed()}.
     */

 *
 * <p>Users of {@code CompletableFuture} will likely want to continue using {@code
 * CompletableFuture}. {@code FluentFuture} is targeted at people who use {@code ListenableFuture},
 * who can't use Java 8, or who want an API more focused than {@code CompletableFuture}. (If you
 * need to adapt between {@code CompletableFuture} and {@code ListenableFuture}, consider <a
 * href="https://github.com/lukas-krecan/future-converter">Future Converter</a>.)
 *

@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)
   */

    /**
     * Returns a new immutable array. The builder can continue to be used after this call, to append
     * more values and build again.
     *
     * <p><b>Performance note:</b> the returned array is backed by the same array as the builder, so
     * no data is copied as part of this step, but this may occupy more memory than strictly
     * necessary. To copy the data to a right-sized backing array, use {@code .build().trimmed()}.
     */