code: public static Socket standardSocket(UrlParser urlParser, String host) throws IOException {
      SocketFactory socketFactory;
      String socketFactoryName = urlParser.getOptions().socketFactory;
      if (socketFactoryName != null) {
        try {
          @SuppressWarnings("unchecked")
          Class<? extends SocketFactory> socketFactoryClass = (Class<? extends SocketFactory>) Class
              .forName(socketFactoryName);
          if (socketFactoryClass != null) {
            Constructor<? extends SocketFactory> constructor = socketFactoryClass.getConstructor();
            socketFactory = constructor.newInstance();
            return socketFactory.createSocket();
          }
        } catch (Exception exp) {
          throw new IOException(
              "Socket factory failed to initialized with option \"socketFactory\" set to \""
                  + urlParser.getOptions().socketFactory + "\"", exp);
        }
      }
      socketFactory = SocketFactory.getDefault();
      return socketFactory.createSocket();
    }
docs: Use standard socket implementation.
  
  @param urlParser url parser
  @param host      host to connect
  @return socket
  @throws IOException in case of error establishing socket.