*/
  @CanIgnoreReturnValue
  public HostAndPort requireBracketsForIPv6() {
    checkArgument(!hasBracketlessColons, "Possible bracketless IPv6 literal: %s", host);
    return this;
  }

  @Override
  public boolean equals(@CheckForNull Object other) {
    if (this == other) {
      return true;
    }
    if (other instanceof HostAndPort) {
      HostAndPort that = (HostAndPort) other;

    assertEquals(123, HostAndPort.fromString("host").getPortOrDefault(123));
  }

  public void testHashCodeAndEquals() {
    HostAndPort hpNoPort1 = HostAndPort.fromString("foo::123");
    HostAndPort hpNoPort2 = HostAndPort.fromString("foo::123");
    HostAndPort hpNoPort3 = HostAndPort.fromString("[foo::123]");
    HostAndPort hpNoPort4 = HostAndPort.fromHost("[foo::123]");

    assertEquals(123, HostAndPort.fromString("host").getPortOrDefault(123));
  }

  public void testHashCodeAndEquals() {
    HostAndPort hpNoPort1 = HostAndPort.fromString("foo::123");
    HostAndPort hpNoPort2 = HostAndPort.fromString("foo::123");
    HostAndPort hpNoPort3 = HostAndPort.fromString("[foo::123]");
    HostAndPort hpNoPort4 = HostAndPort.fromHost("[foo::123]");

        final SMailPostalMotorbike motorbike = new SMailPostalMotorbike();
        final String hostAndPort = fessConfig.getMailSmtpServerMainHostAndPort();
        final List<String> hostPortList = DfStringUtil.splitListTrimmed(hostAndPort, ":");
        motorbike.registerConnectionInfo(hostPortList.get(0), Integer.parseInt(hostPortList.get(1)));

      if (!path.startsWith("/")) {
        path = "/"
      }
      this.path = path

      val scheme = if (socket is SSLSocket) "https" else "http"
      val localPort = socket.localPort
      val hostAndPort =
        headers[":authority"]
          ?: headers["Host"]
          ?: when (val inetAddress = socket.localAddress) {
            is Inet6Address -> "[${inetAddress.hostAddress}]:$localPort"

   */
  public static HostSpecifier fromValid(String specifier) {
    // Verify that no port was specified, and strip optional brackets from
    // IPv6 literals.
    HostAndPort parsedHost = HostAndPort.fromString(specifier);
    Preconditions.checkArgument(!parsedHost.hasPort());
    String host = parsedHost.getHost();

    // Try to interpret the specifier as an IP address. Note we build