RocketMQ--订阅模式

不念不忘少年蓝@ 2023-06-11 13:21 12阅读 0赞

> 创建者

public class OrderedProducer {
        public static void main(String[] args) throws Exception {
            //Instantiate with a producer group name.
            MQProducer producer = new DefaultMQProducer("example_group_name");
            //Launch the instance.
            producer.start();
            String[] tags = new String[] {"TagA", "TagB", "TagC", "TagD", "TagE"};
            for (int i = 0; i < 100; i++) {
                int orderId = i % 10;
                //Create a message instance, specifying topic, tag and message body.
                Message msg = new Message("TopicTestjjj", tags[i % tags.length], "KEY" + i,
                        ("Hello RocketMQ " + i).getBytes(RemotingHelper.DEFAULT_CHARSET));
                SendResult sendResult = producer.send(msg, new MessageQueueSelector() {
                @Override
                public MessageQueue select(List<MessageQueue> mqs, Message msg, Object arg) {
                    Integer id = (Integer) arg;
                    int index = id % mqs.size();
                    return mqs.get(index);
                }
                }, orderId);
    
                System.out.printf("%s%n", sendResult);
            }
            //server shutdown
            producer.shutdown();
        }
    }

> 消费者

public class OrderedConsumer {
        public static void main(String[] args) throws Exception {
            DefaultMQPushConsumer consumer = new DefaultMQPushConsumer("example_group_name");
    
            consumer.setConsumeFromWhere(ConsumeFromWhere.CONSUME_FROM_FIRST_OFFSET);
    
            consumer.subscribe("TopicTest", "TagA || TagC || TagD");
    
            consumer.registerMessageListener(new MessageListenerOrderly() {
    
                AtomicLong consumeTimes = new AtomicLong(0);
                @Override
                public ConsumeOrderlyStatus consumeMessage(List<MessageExt> msgs,
                                                           ConsumeOrderlyContext context) {
                    context.setAutoCommit(false);
                    System.out.printf(Thread.currentThread().getName() + " Receive New Messages: " + msgs + "%n");
                    this.consumeTimes.incrementAndGet();
                    if ((this.consumeTimes.get() % 2) == 0) {
                        return ConsumeOrderlyStatus.SUCCESS;
                    } else if ((this.consumeTimes.get() % 3) == 0) {
                        return ConsumeOrderlyStatus.ROLLBACK;
                    } else if ((this.consumeTimes.get() % 4) == 0) {
                        return ConsumeOrderlyStatus.COMMIT;
                    } else if ((this.consumeTimes.get() % 5) == 0) {
                        context.setSuspendCurrentQueueTimeMillis(3000);
                        return ConsumeOrderlyStatus.SUSPEND_CURRENT_QUEUE_A_MOMENT;
                    }
                    return ConsumeOrderlyStatus.SUCCESS;
    
                }
            });
    
            consumer.start();
    
            System.out.printf("Consumer Started.%n");
        }
    }