如何维护一个TOPIC多个TAG的订阅关系？

[zb315044652]

java-srpingboot-demo版本中订阅者代码：

//项目中加上 @Configuration 注解，这样服务启动时consumer也启动了
public class ConsumerClient {

    @Autowired
    private MqConfig mqConfig;

    @Autowired
    private DemoMessageListener messageListener;

    @Bean(initMethod = "start", destroyMethod = "shutdown")
    public ConsumerBean buildConsumer() {
        ConsumerBean consumerBean = new ConsumerBean();
        //配置文件
        Properties properties = mqConfig.getMqPropertie();
        properties.setProperty(PropertyKeyConst.GROUP_ID, mqConfig.getGroupId());
        //将消费者线程数固定为20个 20为默认值
        properties.setProperty(PropertyKeyConst.ConsumeThreadNums, "20");
        consumerBean.setProperties(properties);

        //订阅关系
        Map<Subscription, MessageListener> subscriptionTable = new HashMap<>();
        Subscription subscription = new Subscription();
        subscription.setTopic(mqConfig.getTopic());
        subscription.setExpression(mqConfig.getTag());
        subscriptionTable.put(subscription, messageListener);
        //订阅多个topic如上面设置

        consumerBean.setSubscriptionTable(subscriptionTable);
        return consumerBean;
    }

}

其中

        Map<Subscription, MessageListener> subscriptionTable = new HashMap<>();
        Subscription subscription = new Subscription();
        subscription.setTopic(mqConfig.getTopic());
        subscription.setExpression(mqConfig.getTag());

如果同一个topic不同的tag，无法加入到subscriptionTable 中，因为Subscription 重写了hashCode equals方法

    @Override
    public int hashCode() {
        final int prime = 31;
        int result = 1;
        result = prime * result + ((topic == null) ? 0 : topic.hashCode());
        return result;
    }

    @Override
    public boolean equals(Object obj) {
        if (this == obj) {
            return true;
        }
        if (obj == null) {
            return false;
        }
        if (getClass() != obj.getClass()) {
            return false;
        }
        Subscription other = (Subscription) obj;
        if (topic == null) {
            if (other.topic != null) {
                return false;
            }
        } else if (!topic.equals(other.topic)) {
            return false;
        }
        return true;
    }

所以对于同一个topic不同的tag的场景，如何去使用？

查询 官方文档

那么如何根据不同的TAG区分不同的业务处理？例如在自己的MessageListener 中区分：

    @Override
    public Action consume(Message message, ConsumeContext context) {
        try {

            message.getTag(); // 根据tag区分不同业务???? 

            return Action.CommitMessage;
        } catch (Exception e) {
            return Action.ReconsumeLater;
        }
    }

[awesometype]

再创建一个ConsumerBean