Vertx sending and receiving using custom object EventBus

Look at the steps of the official document:

Requires a codec, see Source:

Visible built to achieve required data types, it may send another message sent, but if the object is to send custom need to implement the encoding and decoding logic

A custom CODEC

/**
 * 自定义对象编解码器,两个类型可用于消息转换,即发送对象转换为接受需要的对象
 */
public class CustomizeMessageCodec implements MessageCodec<OrderMessage, OrderMessage> {
    /**
     * 将消息实体封装到Buffer用于传输
     * 实现方式：使用对象流从对象中获取Byte数组然后追加到Buffer
     */
    @Override
    public void encodeToWire(Buffer buffer, OrderMessage orderMessage) {
        final ByteArrayOutputStream b = new ByteArrayOutputStream();
        try (ObjectOutputStream o = new ObjectOutputStream(b)){
            o.writeObject(orderMessage);
            o.close();
            buffer.appendBytes(b.toByteArray());
        } catch (IOException e) { e.printStackTrace(); }
    }
    //从Buffer中获取消息对象
    @Override
    public OrderMessage decodeFromWire(int pos, Buffer buffer) {
        final ByteArrayInputStream b = new ByteArrayInputStream(buffer.getBytes());
        OrderMessage msg = null;
        try (ObjectInputStream o = new ObjectInputStream(b)){ msg = (OrderMessage) o.readObject();
        } catch (IOException | ClassNotFoundException e) { e.printStackTrace(); }
        return msg;
    }
    //消息转换
    @Override
    public OrderMessage transform(OrderMessage orderMessage) {
        System.out.println("消息转换---");//可对接受消息进行转换,比如转换成另一个对象等
        orderMessage.setName("姚振");
        return orderMessage;
    }
    @Override
    public String name() { return "myCodec"; }
    //识别是否是用户自定义编解码器,通常为-1
    @Override
    public byte systemCodecID() { return -1; }
    public static MessageCodec create() {
        return new CustomizeMessageCodec();
    }
}

 这里有一个点要注意,nam方法是必须的,且发送的时候一定要指明name

二 发送消息编写

public class ProducerVerticle extends AbstractVerticle {
    @Override
    public void start() throws Exception {
        EventBus eventBus = vertx.eventBus();
        //发布消息(群发)
        eventBus.publish("com.hou", "群发祝福!");
        //发送消息(单发),只会发送注册此地址的一个,采用不严格的轮询算法选择
        DeliveryOptions options = new DeliveryOptions();//设置消息头等
        options.addHeader("some-header", "some-value");
        eventBus.send("com.hou", "单发消息",options,ar->{
            if(ar.succeeded()) System.out.println("收到消费者确认信息:"+ar.result().body());
        });
        //发送自定义对象,需要编解码器
        eventBus.registerCodec(CustomizeMessageCodec.create());//注册编码器
        DeliveryOptions options1 = new DeliveryOptions().setCodecName("myCodec");//必须指定名字
        OrderMessage orderMessage = new OrderMessage();
        orderMessage.setName("侯征");
        eventBus.send("com.hou", orderMessage, options1);
    }
}

 

三 接受消息Verticle编写

public class ConsumerVerticle extends AbstractVerticle {
    @Override
    public void start() throws Exception {
        //每个Vertx实例默认是单例
        EventBus eb = vertx.eventBus();
        //注册处理器,消费com.hou发送的消息
        MessageConsumer<Object> consumer = eb.consumer("com.hou");//订阅地址
        consumer.handler(message -> {//消息处理器
            if(message.body() instanceof OrderMessage){
                System.out.println("接受到对象: " + ((OrderMessage) message.body()).getName());
            }
            System.out.println("我是普通消费者: " + message.body());
            message.reply("收到了!"); // 回复生产者,send才能接受
        }).completionHandler(res -> {//注册完成后通知事件,适用于集群中比较慢的情况下
                System.out.println("注册处理器结果"+res.succeeded());
        });
        //撤销处理器
        //consumer.unregister();
    }
}

 

四 注册部署Verticcle

vertx.deployVerticle(ConsumerVerticle.class.getName());
        TimeUnit.SECONDS.sleep(1);
        vertx.deployVerticle(ProducerVerticle.class.getName());

 

五 测试