netty+springboot实现websocket客户端，客户端注入bean容器，启动boot项目即加载websocket客户端bean，netty版本依赖为4.1.43.Final ，不需要wss安全

首先，需要在pom.xml文件中添加Netty和Spring Boot的依赖：

<dependency>
    <groupId>io.netty</groupId>
    <artifactId>netty-all</artifactId>
    <version>4.1.43.Final</version>
</dependency>

<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-websocket</artifactId>
</dependency>

然后，创建一个WebSocket客户端类，继承自 `ChannelInboundHandlerAdapter`，实现WebSocket协议相关的方法：

@Component
public class WebSocketClient extends ChannelInboundHandlerAdapter {

    private WebSocketClientHandshaker handshaker;
    private ChannelPromise handshakeFuture;

    @Autowired
    private WebSocketClientHandler handler;

    public void connect(String url) throws Exception {
        URI uri = new URI(url);
        String scheme = uri.getScheme() == null ? "ws" : uri.getScheme();
        String host = uri.getHost() == null ? "127.0.0.1" : uri.getHost();
        int port = uri.getPort();
        if (port == -1) {
            if ("ws".equalsIgnoreCase(scheme)) {
                port = 80;
            } else if ("wss".equalsIgnoreCase(scheme)) {
                port = 443;
            }
        }

        if (!"ws".equalsIgnoreCase(scheme) && !"wss".equalsIgnoreCase(scheme)) {
            throw new IllegalArgumentException("Unsupported scheme: " + scheme);
        }

        final WebSocketClientHandler handler = this.handler;
        EventLoopGroup group = new NioEventLoopGroup();
        try {
            Bootstrap bootstrap = new Bootstrap();
            bootstrap.group(group)
                    .option(ChannelOption.SO_KEEPALIVE, true)
                    .channel(NioSocketChannel.class)
                    .handler(new ChannelInitializer<SocketChannel>() {
                        @Override
                        public void initChannel(SocketChannel ch) throws Exception {
                            ChannelPipeline pipeline = ch.pipeline();
                            if ("wss".equalsIgnoreCase(scheme)) {
                                SslContext sslContext = SslContextBuilder.forClient().build();
                                pipeline.addLast(sslContext.newHandler(ch.alloc(), host, port));
                            }
                            pipeline.addLast(new HttpClientCodec(),
                                    new HttpObjectAggregator(8192),
                                    WebSocketClientCompressionHandler.INSTANCE,
                                    handler);
                        }
                    });

            Channel channel = bootstrap.connect(uri.getHost(), port).sync().channel();
            handshaker = WebSocketClientHandshakerFactory.newHandshaker(
                    uri, WebSocketVersion.V13, null, true, new DefaultHttpHeaders());
            handshakeFuture = channel.newPromise();
            handler.setHandshakeFuture(handshakeFuture);

            channel.writeAndFlush(new DefaultHttpRequest(HttpVersion.HTTP_1_1, HttpMethod.GET, uri.getRawPath()))
                    .addListener(new ChannelFutureListener() {
                        @Override
                        public void operationComplete(ChannelFuture future) {
                            if (future.isSuccess()) {
                                handshaker.handshake(future.channel());
                            } else {
                                handshakeFuture.setFailure(future.cause());
                            }
                        }
                    });

            handshakeFuture.sync();
            channel.closeFuture().sync();
        } finally {
            group.shutdownGracefully();
        }
    }

    @Override
    public void channelActive(ChannelHandlerContext ctx) throws Exception {
        handler.setCtx(ctx);
        handshaker.handshake(ctx.channel());
    }

    @Override
    public void channelInactive(ChannelHandlerContext ctx) throws Exception {
        System.out.println("WebSocket Client disconnected!");
        handler.setCtx(null);
    }

    @Override
    public void channelRead(ChannelHandlerContext ctx, Object msg) throws Exception {
        Channel ch = ctx.channel();
        if (!handshaker.isHandshakeComplete()) {
            try {
                handshaker.finishHandshake(ch, (FullHttpResponse) msg);
                System.out.println("WebSocket Client connected!");
                handshakeFuture.setSuccess();
            } catch (WebSocketHandshakeException e) {
                System.out.println("WebSocket Client failed to connect");
                handshakeFuture.setFailure(e);
            }
            return;
        }

        if (msg instanceof FullHttpResponse) {
            FullHttpResponse response = (FullHttpResponse) msg;
            throw new IllegalStateException(
                    "Unexpected FullHttpResponse (getStatus=" + response.status() +
                            ", content=" + response.content().toString(CharsetUtil.UTF_8) + ')');
        }

        WebSocketFrame frame = (WebSocketFrame) msg;
        if (frame instanceof TextWebSocketFrame) {
            TextWebSocketFrame textFrame = (TextWebSocketFrame) frame;
            System.out.println("WebSocket Client received message: " + textFrame.text());
        } else if (frame instanceof PongWebSocketFrame) {
            System.out.println("WebSocket Client received pong");
        } else if (frame instanceof CloseWebSocketFrame) {
            System.out.println("WebSocket Client received closing");
            ch.close();
        }
    }
}

在这个类中，我们注入了一个 `WebSocketClientHandler` 的实例，它也是一个 `ChannelInboundHandlerAdapter`，用于处理WebSocket消息。在 `connect()` 方法中，我们使用Netty创建了一个Bootstrap实例，并设置了一些参数，然后连接到WebSocket服务器。在连接成功后，进行了握手操作，以确保连接正常建立。

下面是 `WebSocketClientHandler` 的实现：

@Component
public class WebSocketClientHandler extends ChannelInboundHandlerAdapter {

    private ChannelHandlerContext ctx;
    private ChannelPromise handshakeFuture;

    public void setCtx(ChannelHandlerContext ctx) {
        this.ctx = ctx;
    }

    public void setHandshakeFuture(ChannelPromise handshakeFuture) {
        this.handshakeFuture = handshakeFuture;
    }

    @Override
    public void userEventTriggered(ChannelHandlerContext ctx, Object evt) throws Exception {
        if (evt == WebSocketClientProtocolHandler.ClientHandshakeStateEvent.HANDSHAKE_COMPLETE) {
            handshakeFuture.setSuccess();
        } else {
            super.userEventTriggered(ctx, evt);
        }
    }

    @Override
    public void channelRead(ChannelHandlerContext ctx, Object msg) throws Exception {
        // Handle WebSocket message
    }

    // Other methods
}

在这个类中，我们重写了 `channelRead()` 方法，用于处理WebSocket消息。我们也保存了当前的 `ChannelHandlerContext` 和握手操作的 `ChannelPromise`，以便在连接成功后进行操作。

最后，在Spring Boot的主类中，可以通过注入 `WebSocketClient` 的方式来启动WebSocket客户端：

@SpringBootApplication
public class Application {

    @Autowired
    private WebSocketClient webSocketClient;

    public static void main(String[] args) throws Exception {
        SpringApplication.run(Application.class, args);
    }

    @EventListener(ApplicationReadyEvent.class)
    public void connect() throws Exception {
        webSocketClient.connect("ws://localhost:8080/websocket");
    }
}

在 `connect()` 方法中，我们调用了 `WebSocketClient` 的 `connect()` 方法，来连接到WebSocket服务器。注意，这个方法是阻塞的，直到连接关闭或连接失败。

这样，我们就成功地使用Netty和Spring Boot实现了一个WebSocket客户端，并且可以将其注入到Spring Boot的Bean容器中，以方便管理和使用。