* to implement the related methods as well. Finally, two collection views are provided: {@link
 * #elementSet} contains the distinct elements of the multiset "with duplicates collapsed", and
 * {@link #entrySet} is similar but contains {@link Entry Multiset.Entry} instances, each providing
 * both a distinct element and the count of that element.
 *

        assertThrows(IllegalArgumentException.class, () -> builder.buildOrThrow());
    // We don't really care which values the exception message contains, but they should be
    // different from each other. If buildKeepingLast() collapsed duplicates, that might end up not
    // being true.
    Pattern pattern = Pattern.compile("Multiple entries with same key: four=(.*) and four=(.*)");
    assertThat(expected).hasMessageThat().matches(pattern);

   * @param isFinalPart Is this the final (rightmost) domain part?
   * @return Whether the part is valid
   */
  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;
    }

    /*

   * href="http://tools.ietf.org/html/rfc4291#section-2.5.5.2">RFC 4291</a>.
   *
   * <p>Note: This method takes a {@code String} argument because {@link InetAddress} automatically
   * collapses mapped addresses to IPv4. (It is actually possible to avoid this using one of the
   * obscure {@link Inet6Address} methods, but it would be unwise to depend on such a
   * poorly-documented feature.)
   *

labels.facet_filetype_shell=Shell Script
labels.facet_filetype_vb=Visual Basic
labels.virtual_hosts=Virtual Hosts
labels.virtual_host=Virtual Host
labels.virtual_host_value=Virtual Hosts
labels.result_collapsed=Similar Result Collapsed
labels.log_level=Log Level
labels.crawling_info_thread_dump=Thread Dump
labels.key_match_urls=Urls
labels.data_crawling_button_create=Create
labels.dict_stemmeroverride_configuration=Stemmer Override List

labels.facet_filetype_shell=Shell Script
labels.facet_filetype_vb=Visual Basic
labels.virtual_hosts=Virtual Hosts
labels.virtual_host=Virtual Host
labels.virtual_host_value=Virtual Hosts
labels.result_collapsed=Similar Result Collapsed
labels.log_level=Log Level
labels.crawling_info_thread_dump=Thread Dump
labels.key_match_urls=Urls
labels.dict_stemmeroverride_configuration=Stemmer Override List
labels.dict_stemmeroverride_title=Stemmer Override List

labels.default_sort_value=Default Sort Value
labels.virtual_host_value=Virtual Hosts
labels.append_query_param_enabled=Append Params to URL
labels.login_required=Login Required
labels.result_collapsed=Similar Result Collapsed
labels.login_link=Login Link
labels.thumbnail=Thumbnail View
labels.ignore_failure_type=Excluded Failure Type
labels.failure_count_threshold=Failure Count Threshold
labels.popular_word_word_enabled=Popular Word Response

   * href="http://tools.ietf.org/html/rfc4291#section-2.5.5.2">RFC 4291</a>.
   *
   * <p>Note: This method takes a {@code String} argument because {@link InetAddress} automatically
   * collapses mapped addresses to IPv4. (It is actually possible to avoid this using one of the
   * obscure {@link Inet6Address} methods, but it would be unwise to depend on such a
   * poorly-documented feature.)
   *

          return finishCollapseFrom(sequence, i + 1, len, replacement, builder, true);
        }
      }
    }
    // no replacement needed
    return sequence.toString();
  }

  /**
   * Collapses groups of matching characters exactly as {@link #collapseFrom} does, except that
   * groups of matching BMP characters at the start or end of the sequence are removed without
   * replacement.
   */

    /** The key of the message: Login Required */
    public static final String LABELS_login_required = "{labels.login_required}";

    /** The key of the message: Similar Result Collapsed */
    public static final String LABELS_result_collapsed = "{labels.result_collapsed}";

    /** The key of the message: Login Link */
    public static final String LABELS_login_link = "{labels.login_link}";