.addEqualityGroup(hashFunction2)
            .testEquals();

        assertEquals(hashFunction1a.toString(), hashFunction1b.toString());
      }
    }
  }

  // Parity tests taken from //util/hash/hash_unittest.cc

 * reference. It allows you to represent "a {@code T} that must be present" and a "a {@code T} that
 * might be absent" as two distinct types in your program, which can aid clarity.
 *
 * <p>Some uses of this class include
 *
 * <ul>
 *   <li>As a method return type, as an alternative to returning {@code null} to indicate that no
 *       value was available

 *   <li>Use of {@link java.util.Objects#requireNonNull(Object)} is generally discouraged, since
 *       {@link #verifyNotNull(Object)} and {@link Preconditions#checkNotNull(Object)} perform the
 *       same function with more clarity.
 * </ul>
 *
 * <h3>Warning about performance</h3>
 *
 * <p>Remember that parameter values for message construction must all be computed eagerly, and

            .addEqualityGroup(hashFunction2)
            .testEquals();

        assertEquals(hashFunction1a.toString(), hashFunction1b.toString());
      }
    }
  }

  // Parity tests taken from //util/hash/hash_unittest.cc

 *   <li>Use of {@link java.util.Objects#requireNonNull(Object)} is generally discouraged, since
 *       {@link #verifyNotNull(Object)} and {@link Preconditions#checkNotNull(Object)} perform the
 *       same function with more clarity.
 * </ul>
 *
 * <h3>Warning about performance</h3>
 *
 * <p>Remember that parameter values for message construction must all be computed eagerly, and

   */
  private static boolean validatePart(String part, boolean isFinalPart) {

    // These tests could be collapsed into one big boolean expression, but
    // they have been left as independent tests for clarity.

    if (part.length() < 1 || part.length() > MAX_DOMAIN_PART_LENGTH) {
      return false;
    }

    /*
     * GWT claims to support java.lang.Character's char-classification methods, but it actually only

      SortedSetMultimap<K, V> multimap) {
    return (Map<K, SortedSet<V>>) (Map<K, ?>) multimap.asMap();
  }

  /**
   * Returns {@link Multimap#asMap multimap.asMap()}. This is provided for parity with the other
   * more strongly-typed {@code asMap()} implementations.
   *
   * @since 15.0
   */
  public static <K extends @Nullable Object, V extends @Nullable Object>

 * reference. It allows you to represent "a {@code T} that must be present" and a "a {@code T} that
 * might be absent" as two distinct types in your program, which can aid clarity.
 *
 * <p>Some uses of this class include
 *
 * <ul>
 *   <li>As a method return type, as an alternative to returning {@code null} to indicate that no
 *       value was available