Sending and Receiving Order Messages

RocketMQ provides a type of order message that is produced and consumed in order. The order message includes global order messages and partition order messages, as follows:

Global order message: All messages guarantee FIFO production and consumption, which is actually a single queue.
Partition order message: Using the Sharding Key provided by the user for block partitioning, the same partition messages are published and consumed in strict FIFO order.

The production and consumption code of the two types of sequence messages are consistent.

Send Order Messages

import java.io.UnsupportedEncodingException;
import java.util.List;
import org.apache.rocketmq.client.exception.MQBrokerException;
import org.apache.rocketmq.client.exception.MQClientException;
import org.apache.rocketmq.client.producer.DefaultMQProducer;
import org.apache.rocketmq.client.producer.MQProducer;
import org.apache.rocketmq.client.producer.MessageQueueSelector;
import org.apache.rocketmq.client.producer.SendResult;
import org.apache.rocketmq.common.message.Message;
import org.apache.rocketmq.common.message.MessageQueue;
import org.apache.rocketmq.remoting.common.RemotingHelper;
import org.apache.rocketmq.remoting.exception.RemotingException;
import org.apache.rocketmq.acl.common.AclClientRPCHook;
import org.apache.rocketmq.acl.common.SessionCredentials;
import org.apache.rocketmq.remoting.RPCHook;

public class Producer {
    // Instance access uses a public and private key, which can be obtained on the instance token management page
    private static final String ACCESS_KEY = "xxx";
    private static final String SECRET_KEY = "xxx";

    static RPCHook getAclRPCHook() {
        return new AclClientRPCHook(new SessionCredentials(ACCESS_KEY, SECRET_KEY));
    }
    public static void main(String[] args) throws UnsupportedEncodingException {
        try {
            // "ProducerGroupName" is the production group, users can use the production Group created by the console or customize it.
            DefaultMQProducer producer = new DefaultMQProducer("ProducerGroupName", getAclRPCHook());
            // Instance access address, can be obtained from the instance list page
            producer.setNamesrvAddr("1.1.1.1:9876");
            producer.start();

            String[] tags = new String[] {"TagA", "TagB", "TagC", "TagD", "TagE"};
            for (int i = 0; i < 100; i++) {
                int orderId = i % 10;
                Message msg =
                    new Message("Topic_Name", tags[i % tags.length], "Message_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);
            }

            producer.shutdown();
        } catch (MQClientException | RemotingException | MQBrokerException | InterruptedException e) {
            e.printStackTrace();
        }
    }
}

Subscribe Order Messages

import java.util.List;
import java.util.concurrent.atomic.AtomicLong;
import org.apache.rocketmq.client.consumer.DefaultMQPushConsumer;
import org.apache.rocketmq.client.consumer.listener.ConsumeOrderlyContext;
import org.apache.rocketmq.client.consumer.listener.ConsumeOrderlyStatus;
import org.apache.rocketmq.client.consumer.listener.MessageListenerOrderly;
import org.apache.rocketmq.client.consumer.rebalance.AllocateMessageQueueAveragely;
import org.apache.rocketmq.client.exception.MQClientException;
import org.apache.rocketmq.common.message.MessageExt;
import org.apache.rocketmq.acl.common.AclClientRPCHook;
import org.apache.rocketmq.acl.common.SessionCredentials;
import org.apache.rocketmq.remoting.RPCHook;

public class Consumer {
    // Instance access uses a public and private key, which can be obtained from the instance token management page
    private static final String ACCESS_KEY = "xxx";
    private static final String SECRET_KEY = "xxx";

    static RPCHook getAclRPCHook() {
        return new AclClientRPCHook(new SessionCredentials(ACCESS_KEY, SECRET_KEY));
    }

    public static void main(String[] args) throws MQClientException {
        // "GROUP_NAME" is the consumer group, which can be obtained from the instance Group management page.
        DefaultMQPushConsumer consumer = new DefaultMQPushConsumer("GROUP_NAME", getAclRPCHook(), new AllocateMessageQueueAveragely());
        // Instance access address, can be obtained from the instance list page
        consumer.setNamesrvAddr("1.1.1.1:8100");
        consumer.subscribe("Topic_Name", "TagA || TagC || TagD");

        consumer.registerMessageListener(new MessageListenerOrderly() {
            AtomicLong consumeTimes = new AtomicLong(0);

            @Override
            public ConsumeOrderlyStatus consumeMessage(List<MessageExt> msgs, ConsumeOrderlyContext context) {
                context.setAutoCommit(true);
                System.out.printf("%s Receive New Messages: %s %n", Thread.currentThread().getName(), msgs);
                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");
    }
}

Receive and Send Ordinary Messages Receive and Send Transaction Messages