基于netty的tcp服务端接收硬件16进制数据

基于netty的tcp服务端接收硬件16进制数据

最近项目中需要后端对接硬件设备,该硬件设备是硬件厂商自己的编码规则,采用的HEX16进制编码,下面将自己对接过程进行总结方便之后再次利用,有错误之处还请大家进行指正.

搭建后端tcp服务

netty服务

@Component
@Slf4j
public class NettyServer {

    /**
     * boss 线程组用于处理连接工作
     */
    private EventLoopGroup boss = new NioEventLoopGroup();
    /**
     * work 线程组用于数据处理
     */
    private EventLoopGroup work = new NioEventLoopGroup();

    // @Value("${netty.port}")
    // private Integer port;

    /**
     * 启动Netty Server
     *
     * @throws InterruptedException
     */
    @PostConstruct
    public void start() throws InterruptedException {
        ServerBootstrap bootstrap = new ServerBootstrap();
        ServerBootstrap serverBootstrap = bootstrap.group(boss, work)
                // 指定Channel
                .channel(NioServerSocketChannel.class)
                //使用指定的端口设置套接字地址
                // .localAddress(new InetSocketAddress(port))
                .localAddress(new InetSocketAddress(7788))
                //服务端可连接队列数,对应TCP/IP协议listen函数中backlog参数
                .option(ChannelOption.SO_BACKLOG, 1024)
                //设置TCP长连接,一般如果两个小时内没有数据的通信时,TCP会自动发送一个活动探测数据报文
                .childOption(ChannelOption.SO_KEEPALIVE, true)
                //将小的数据包包装成更大的帧进行传送，提高网络的负载
                .childOption(ChannelOption.TCP_NODELAY, true)
                .childHandler(new ServerChannelInitializer());
        ChannelFuture future = bootstrap.bind().sync();
        if (future.isSuccess()) {
            log.info("启动 Netty Server");
        }
    }

    @PreDestroy
    public void destory() throws InterruptedException {
        boss.shutdownGracefully().sync();
        work.shutdownGracefully().sync();
        log.info("关闭Netty");
    }
}

netty的服务处理类NettyServerHandler

@Slf4j
public class NettyServerHandler extends ChannelInboundHandlerAdapter {
    /**
     * 客户端连接会触发
     */
    @Override
    public void channelActive(ChannelHandlerContext ctx) throws Exception {
        log.info("Channel active......");
    }

    /**
     * 客户端发消息会触发
     */
    @Override
    public void channelRead(ChannelHandlerContext ctx, Object msg) throws Exception {
        log.info("服务器收到消息: {}", msg.toString());
        ctx.write("我是服务端，我收到你的消息了！");
        ctx.flush();
    }

    /**
     * 发生异常触发
     */
    @Override
    public void exceptionCaught(ChannelHandlerContext ctx, Throwable cause) throws Exception {
        cause.printStackTrace();
        ctx.close();
    }
}

netty服务端编解码类ServerChannelInitializer

public class ServerChannelInitializer extends ChannelInitializer<SocketChannel> {
    @Override
    protected void initChannel(SocketChannel socketChannel) throws Exception {
        //添加编解码
        socketChannel.pipeline().addLast("decoder", new StringDecoder(CharsetUtil.UTF_8));
        socketChannel.pipeline().addLast("encoder", new StringDecoder(CharsetUtil.UTF_8));
        socketChannel.pipeline().addLast(new NettyServerHandler());
    }
}

上述3个类搭建出来就是一个tcp的服务端,但是对于ServerChannelInitializer类中的编码规则我们需要设置的.因为是基于16进制传输的数据,采用这个编码规则会存在乱码情况,所以我们需要编写MyDecoder.

代码如下(MyDecoder):

public class MyDecoder extends ByteToMessageDecoder {

    @Override
    protected void decode(ChannelHandlerContext ctx, ByteBuf buffer, List<Object> out) throws Exception {
        //创建字节数组,buffer.readableBytes可读字节长度
        byte[] b = new byte[buffer.readableBytes()];
        //复制内容到字节数组b
        buffer.readBytes(b);
        //字节数组转字符串
        String str = new String(b);
        out.add(toHexString1(b));
    }


    public static String toHexString1(byte[] b) {
        StringBuffer buffer = new StringBuffer();
        for (int i = 0; i < b.length; ++i) {
            buffer.append(toHexString1(b[i]));
        }
        return buffer.toString();
    }

    public static String toHexString1(byte b) {
        String s = Integer.toHexString(b & 0xFF);
        if (s.length() == 1) {
            return "0" + s.toUpperCase();
        } else {
            return s.toUpperCase();
        }
    }
}

然后将ServerChannelInitializer类中的编码修改为自定义的编码,修改后代码如下:

public class ServerChannelInitializer extends ChannelInitializer<SocketChannel> {
    @Override
    protected void initChannel(SocketChannel socketChannel) throws Exception {
        //添加编解码
        socketChannel.pipeline().addLast("decoder", new MyDecoder());
        socketChannel.pipeline().addLast("encoder", new StringDecoder(CharsetUtil.UTF_8));
        socketChannel.pipeline().addLast(new NettyServerHandler());
    }
}

总结

至此,接受到的数据为正常数据,接收到数据后,会进行数据的解析.上述所有仅仅是本人的记录,如果对于大家有帮助那真是非常荣幸,如果有错误之处,或者更好的建议意见,如果可以,请多多指教.