code: public static HttpServer<ByteBuf, ByteBuf> newServer(int port, EventLoopGroup serverGroup,
                                                           EventLoopGroup clientGroup,
                                                           Class<? extends ServerChannel> channelClass) {
          return _newServer(TcpServer.newServer(port, serverGroup, clientGroup, channelClass));
      }
docs: Creates a new server using the passed port.
  
  @param port Port for the server. {@code 0} to use ephemeral port.
  @param serverGroup Eventloop group to be used for server sockets.
  @param clientGroup Eventloop group to be used for client sockets.
  @param channelClass The class to be used for server channel.
  
  @return A new {@link HttpServer}