final Handshake selected = handshaker;
if (upgradeListener == null) {
exchange.upgradeChannel(new HttpUpgradeListener() {
@Override
public void handleUpgrade(StreamConnection streamConnection, HttpServerExchange exchange) {
WebSocketChannel channel = selected.createChannel(facade, streamConnection, facade.getBufferPool());
callback.onConnect(facade, channel);
}
});
} else {
exchange.upgradeChannel(upgradeListener);