code: private void handleWebSocketHandshake(FullHttpRequest fullHttpRequest, ChannelHandlerContext ctx)
              throws WebSocketConnectorException {
          String extensionsHeader = fullHttpRequest.headers().getAsString(HttpHeaderNames.SEC_WEBSOCKET_EXTENSIONS);
          DefaultWebSocketHandshaker webSocketHandshaker =
                  new DefaultWebSocketHandshaker(ctx, serverConnectorFuture, fullHttpRequest, fullHttpRequest.uri(),
                                                 extensionsHeader != null);
  
          // Setting common properties to handshaker
          webSocketHandshaker.setHttpCarbonRequest(setupHttpCarbonRequest(fullHttpRequest, ctx));
  
          ctx.channel().config().setAutoRead(false);
          serverConnectorFuture.notifyWebSocketListener(webSocketHandshaker);
      }
docs: Handle the WebSocket handshake.
  
  @param fullHttpRequest {@link HttpRequest} of the request.