code: public UrlBuilder withHost(String host) {
          if (host == null || host.isEmpty()) {
              this.host = null;
          } else {
              with(host, UrlTokenizerState.SCHEME_OR_HOST);
          }
          return this;
      }
docs: Set the host that will be used to build the final URL.
  @param host The host that will be used to build the final URL.
  @return This UrlBuilder so that multiple setters can be chained together.