~~~ public static void main(String[] args) throws Exception { EventLoopGroup boss = new NioEventLoopGroup(); EventLoopGroup worker = new NioEventLoopGroup(); try{ ServerBootstrap bootstrap = new ServerBootstrap(); bootstrap.group(boss, worker) .channel(NioServerSocketChannel.class) .childHandler(new WebsocketChannelInitalizer()); ChannelFuture future = bootstrap.bind(8899).sync(); future.channel().closeFuture().sync(); }finally { boss.shutdownGracefully(); worker.shutdownGracefully(); } } ~~~