netty websocket

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使用netty构建websocket服务器

开启服务

public class NettyServer {
    private final int port;
 
    public NettyServer(int port) {
        this.port = port;
    }
 
    public void start() throws Exception {
        EventLoopGroup bossGroup = new NioEventLoopGroup();
 
        EventLoopGroup group = new NioEventLoopGroup();
        try {
            ServerBootstrap sb = new ServerBootstrap();
            sb.option(ChannelOption.SO_BACKLOG, 1024);
            sb.group(group, bossGroup) // 绑定线程池
                    .channel(NioServerSocketChannel.class) // 指定使用的channel
                    .localAddress(this.port)// 绑定监听端口
                    .childHandler(new ChannelInitializer<SocketChannel>() { // 绑定客户端连接时候触发操作
 
                        @Override
                        protected void initChannel(SocketChannel ch) throws Exception {
                            System.out.println("收到新连接");
                            //websocket协议本身是基于http协议的，所以这边也要使用http解编码器
                            ch.pipeline().addLast(new HttpServerCodec());
                            //以块的方式来写的处理器
                            ch.pipeline().addLast(new ChunkedWriteHandler());
                            ch.pipeline().addLast(new HttpObjectAggregator(8192));
                            ch.pipeline().addLast(new MyWebSocketHandler());
                            ch.pipeline().addLast(new WebSocketServerProtocolHandler("/ws", "WebSocket", true, 65536 * 10));
                        }
                    });
            ChannelFuture cf = sb.bind().sync(); // 服务器异步创建绑定
            System.out.println(NettyServer.class + " 启动正在监听： " + cf.channel().localAddress());
            cf.channel().closeFuture().sync(); // 关闭服务器通道
        } finally {
            group.shutdownGracefully().sync(); // 释放线程池资源
            bossGroup.shutdownGracefully().sync();
        }
    }
}

通道处理

public class MyWebSocketHandler extends SimpleChannelInboundHandler<TextWebSocketFrame> {

    @Override
    public void channelActive(ChannelHandlerContext ctx) throws Exception {
        System.out.println("与客户端建立连接，通道开启！");

        //添加到channelGroup通道组
        MyChannelHandlerPool.channelGroup.add(ctx.channel());
    }

    @Override
    public void channelInactive(ChannelHandlerContext ctx) throws Exception {
        System.out.println("与客户端断开连接，通道关闭！");
        //添加到channelGroup 通道组
        MyChannelHandlerPool.channelGroup.remove(ctx.channel());
    }

    @Override
    public void channelRead(ChannelHandlerContext ctx, Object msg) throws Exception {
        //首次连接是FullHttpRequest，处理参数 by zhengkai.blog.csdn.net
        if (null != msg && msg instanceof FullHttpRequest) {
            FullHttpRequest request = (FullHttpRequest) msg;
            String uri = request.uri();

            Map paramMap=getUrlParams(uri);
            System.out.println("接收到的参数是："+JSON.toJSONString(paramMap));
            //如果url包含参数，需要处理
            if(uri.contains("?")){
                String newUri=uri.substring(0,uri.indexOf("?"));
                System.out.println(newUri);
                request.setUri(newUri);
            }

        }else if(msg instanceof TextWebSocketFrame){
            //正常的TEXT消息类型
            TextWebSocketFrame frame=(TextWebSocketFrame)msg;
            System.out.println("客户端收到服务器数据：" +frame.text());
            sendAllMessage(frame.text());
        }
        super.channelRead(ctx, msg);
    }

    @Override
    protected void channelRead0(ChannelHandlerContext channelHandlerContext, TextWebSocketFrame textWebSocketFrame) throws Exception {

    }

    private void sendAllMessage(String message){
        //收到信息后，群发给所有channel
        MyChannelHandlerPool.channelGroup.writeAndFlush( new TextWebSocketFrame(message));
    }

    private static Map getUrlParams(String url){
        Map<String,String> map = new HashMap<>();
        url = url.replace("?",";");
        if (!url.contains(";")){
            return map;
        }
        if (url.split(";").length > 0){
            String[] arr = url.split(";")[1].split("&");
            for (String s : arr){
                String key = s.split("=")[0];
                String value = s.split("=")[1];
                map.put(key,value);
            }
            return  map;

        }else{
            return map;
        }
    }
}

使用

后端有做参数截取，url里可以直接放参数

socket = new WebSocket("ws://127.0.0.1:12345/ws?uid=666&gid=777");

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