WebSocketServerHandshakerFactory factory = new WebSocketServerHandshakerFactory(
getWebSocketLocation(req), null, false);
WebSocketServerHandshaker handshaker = factory.newHandshaker(req);
if (handshaker != null) {
handshaker.handshake(channel, req);
connectClient(channel, sessionId);
} else {
factory.sendUnsupportedWebSocketVersionResponse(ctx.getChannel());
}
}