code: public final TcpClient doOnConnect(Consumer<? super Bootstrap> doOnConnect) {
  		Objects.requireNonNull(doOnConnect, "doOnConnect");
  		return new TcpClientDoOn(this, doOnConnect, null, null);
  	}
docs: Setup a callback called when {@link Channel} is about to connect.
  
  @param doOnConnect a runnable observing connected events
  
  @return a new {@link TcpClient}