code: public CookieBuilder withDomain(String domain) {
          if (domain != null && domain.contains(":")) {
              throw new IllegalArgumentException("The domain value should only be a host name (and should not include the scheme or the port)");
          }
          this.domain = domain;
          return this;
      }
docs: <p>Sets the host that clients should send the cookie over. By default it is the current domain (but not subdomains).</p>
  <p>To allow sub-domains, specify the current domain (e.g. with <code>request.uri().getHost()</code>).</p>
  @param domain The host part of a URL (without scheme or port), e.g. <code>example.org</code>
  @return This builder