code: public WebSocketClient newClient(final URI url, final WebSocketCallback callback) {
          ClientBootstrap bootstrap = new ClientBootstrap(socketChannelFactory);
  
          String protocol = url.getScheme();
          if (!protocol.equals("ws") && !protocol.equals("wss")) {
              throw new IllegalArgumentException("Unsupported protocol: " + protocol);
          }
  
          final WebSocketClientHandler clientHandler = new WebSocketClientHandler(bootstrap, url, callback);
  
          bootstrap.setPipelineFactory(new ChannelPipelineFactory() {
              public ChannelPipeline getPipeline() throws Exception {
                  ChannelPipeline pipeline = Channels.pipeline();
                  pipeline.addLast("decoder", new HttpResponseDecoder());
                  pipeline.addLast("encoder", new HttpRequestEncoder());
                  pipeline.addLast("ws-handler", clientHandler);
                  return pipeline;
              }
          });
  
          return clientHandler;
      }
docs: Create a new WebSocket client
  @param url URL to connect to.
  @param callback Callback interface to receive events
  @return A WebSocket client. Call {@link WebSocketClient#connect()} to connect.