netty 起 Http server

public class HttpServer {
    private final static Logger logger = LoggerFactory.getLogger(HttpServer.class);
    private final int port = 5515;

    private final EventLoopGroup bossGroup = new NioEventLoopGroup();
    private final EventLoopGroup workerGroup = new NioEventLoopGroup();

    public void start() {
        ServerBootstrap bootstrap = new ServerBootstrap()
                .group(bossGroup, workerGroup)
                .channel(NioServerSocketChannel.class)
                .option(ChannelOption.SO_BACKLOG, 512)
                .childHandler(new ChannelInitializer() {
                    @Override
                    protected void initChannel(SocketChannel ch) throws Exception {
                        ch.pipeline().addLast(new HttpServerCodec());
                        ch.pipeline().addLast(new HttpObjectAggregator(512 * 1024));
                        ch.pipeline().addLast(new HttpRequestHandler());
                    }
                });
        try {
            ChannelFuture bindFuture = bootstrap.bind(port).sync();
            bindFuture.channel().closeFuture().addListener(future -> {
                bossGroup.shutdownGracefully();
                workerGroup.shutdownGracefully();
            });
            logger.info("{} is started on port {}.", this.getClass().getSimpleName(), port);
        } catch (Exception e) {
            logger.error("{} starts failed！", this.getClass().getSimpleName(), e);
        }
    }

    public void stop() {
        logger.info("{} stopped.", this.getClass().getSimpleName());
        bossGroup.shutdownGracefully();
        workerGroup.shutdownGracefully();
    }

    class HttpRequestHandler extends SimpleChannelInboundHandler {
        @Override
        protected void channelRead0(ChannelHandlerContext ctx, FullHttpRequest req) throws Exception {
            String uri = req.uri(); // 路径
            String msg = "hello world";
            FullHttpResponse response = new DefaultFullHttpResponse(
                    HttpVersion.HTTP_1_1,
                    HttpResponseStatus.OK,
                    Unpooled.copiedBuffer(msg, CharsetUtil.UTF_8));
//            response.headers().set(HttpHeaderNames.CONTENT_TYPE, "application/json; charset=UTF-8");
            response.headers().set(HttpHeaderNames.CONTENT_TYPE, "text/html; charset=UTF-8");
            ctx.writeAndFlush(response).addListener(ChannelFutureListener.CLOSE);
        }
    }
}