netty框架怎么调用webSocket服务方法

使用Netty框架调用WebSocket服务方法的步骤如下：

1. 导入相关依赖
在Maven的pom.xml文件中加入以下依赖：

<dependency>
    <groupId>io.netty</groupId>
    <artifactId>netty-all</artifactId>
    <version>4.1.42.Final</version>
</dependency>
<dependency>
    <groupId>io.netty</groupId>
    <artifactId>netty-transport-native-epoll</artifactId>
    <version>4.1.42.Final</version>
    <classifier>linux-x86_64</classifier>
</dependency>
<dependency>
    <groupId>io.netty</groupId>
    <artifactId>netty-transport-native-kqueue</artifactId>
    <version>4.1.42.Final</version>
    <classifier>osx-x86_64</classifier>
</dependency>

2. 编写WebSocket服务类
创建一个类来实现WebSocket服务，使用Netty的WebSocketServerHandler类来处理WebSocket消息。在这个类中，我们需要实现以下方法：

public class WebSocketServer extends SimpleChannelInboundHandler<WebSocketFrame> {
    // 连接建立时触发
    @Override
    public void channelActive(ChannelHandlerContext ctx) throws Exception {
        // TODO
    }

    // 连接关闭时触发
    @Override
    public void channelInactive(ChannelHandlerContext ctx) throws Exception {
        // TODO
    }

    // 处理WebSocket帧消息
    @Override
    protected void channelRead0(ChannelHandlerContext ctx, WebSocketFrame msg) throws Exception {
        // TODO
    }

    // 异常处理
    @Override
    public void exceptionCaught(ChannelHandlerContext ctx, Throwable cause) throws Exception {
        // TODO
    }
}

3. 启动WebSocket服务
在main方法中启动WebSocket服务：

public static void main(String[] args) throws Exception {
    EventLoopGroup bossGroup = new NioEventLoopGroup();
    EventLoopGroup workerGroup = new NioEventLoopGroup();
    try {
        ServerBootstrap bootstrap = new ServerBootstrap();
        bootstrap.group(bossGroup, workerGroup)
                 .channel(NioServerSocketChannel.class)
                 .childHandler(new ChannelInitializer<SocketChannel>() {
                     @Override
                     public void initChannel(SocketChannel ch) throws Exception {
                         ChannelPipeline pipeline = ch.pipeline();
                         pipeline.addLast(new HttpServerCodec());
                         pipeline.addLast(new ChunkedWriteHandler());
                         pipeline.addLast(new HttpObjectAggregator(65536));
                         pipeline.addLast(new WebSocketServerProtocolHandler("/websocket"));
                         pipeline.addLast(new WebSocketServer());
                     }
                 });

        ChannelFuture f = bootstrap.bind(8080).sync();
        f.channel().closeFuture().sync();
    } finally {
        bossGroup.shutdownGracefully();
        workerGroup.shutdownGracefully();
    }
}

4. 调用WebSocket服务方法
使用WebSocket客户端来调用WebSocket服务方法：

WebSocketClient client = new WebSocketClient();
client.connect(new URI("ws://localhost:8080/websocket"), new WebSocketHandler() {
    @Override
    public void onOpen(ServerHandshake handshake) {
        // 连接建立时触发
    }

    @Override
    public void onMessage(String message) {
        // 收到消息时触发
    }

    @Override
    public void onClose(int code, String reason, boolean remote) {
        // 连接关闭时触发
    }

    @Override
    public void onError(Exception ex) {
        // 异常处理
    }
});

client.send("hello world"); // 调用WebSocket服务方法