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RocketMQ生产消费模型选择

一. 生产者,根据某个标识将消息放到同一个队列中

在发送消息时,使用SelectMessageQueueByHash,该类根据传入进去的arg,进行hash计算,将消息分配到相应的队列中。

public class Producer {

    public static void main(String[] args) throws MQClientException {

        DefaultMQProducer producer = new DefaultMQProducer("ProducerGroupName");
        producer.setNamesrvAddr("10.130.41.36:9876");
        producer.setInstanceName("Producer");
        producer.setVipChannelEnabled(false);
        producer.start();

        String[] tags = {"tagA","tagB"};

        for (int i = 1; i <= 10; i++) {
            try {
                Message msg = new Message("TopicTest",tags[i%tags.length],"key1"+i,("订单一号" + i).getBytes());
                SendResult sendResult = producer.send(msg, new SelectMessageQueueByHash(),1);
                System.out.println(sendResult);
            } catch (Exception e) {
                e.printStackTrace();
            }
        }
        for (int i = 1; i <= 10; i++) {
            try {
                Message msg = new Message("TopicTest",tags[i%tags.length],"key2"+i,("订单二号" + i).getBytes());
                SendResult sendResult = producer.send(msg, new SelectMessageQueueByHash(),2);
                System.out.println(sendResult);
            } catch (Exception e) {
                e.printStackTrace();
            }
        }
        for (int i = 1; i <= 10; i++) {
            try {
                Message msg = new Message("TopicTest",tags[i%tags.length],"key3"+i,("订单三号" + i).getBytes());
                SendResult sendResult = producer.send(msg, new SelectMessageQueueByHash(),3);
                System.out.println(sendResult);
            } catch (Exception e) {
                e.printStackTrace();
            }
        }
        producer.shutdown();
    }
}

  上述代码执行后Topic队列中的内容:

 

二. 消费者

(1). 顺序消费

使用MessageListenerOrderly,顺序消费同一个队列中的数据,只有第一个数据消费成功了才会消费第二个数据。

模拟在消费某个队列中的数据时出现了阻塞状态。

public class ConsumerOrderly {
    public static void main(String[] args) throws InterruptedException,
            MQClientException {

        DefaultMQPushConsumer consumer = new DefaultMQPushConsumer("ConsumerGroupName");
        consumer.setNamesrvAddr("10.130.41.36:9876");
        consumer.setInstanceName("Consumer1");
        consumer.setMessageModel(MessageModel.CLUSTERING);
        consumer.subscribe("TopicTest", "*");

        consumer.registerMessageListener(new MessageListenerOrderly() {
            @Override
            public ConsumeOrderlyStatus consumeMessage(List<MessageExt> msgs, ConsumeOrderlyContext context) {
                //设置自动提交,如果不设置自动提交就算返回SUCCESS,消费者关闭重启 还是会重复消费的
                context.setAutoCommit(true);
                try {
                    for (MessageExt msg:msgs) {
                        String msgKey = msg.getKeys();
                        if(msgKey.equals("key13") || msgKey.equals("key22")){
                            Thread.sleep(1000);
                        }
                        System.out.println(" 消费者1 ==> 当前线程:"+Thread.currentThread().getName()+" ,quenuID: "+msg.getQueueId()+ " ,content: " + new String(msg.getBody()));
                    }
                } catch (Exception e) {
                    e.printStackTrace();
                    //如果出现异常,消费失败,挂起消费队列一会会,稍后继续消费
                    return ConsumeOrderlyStatus.SUSPEND_CURRENT_QUEUE_A_MOMENT;
                }

                //消费成功
                return ConsumeOrderlyStatus.SUCCESS;
            }
        });

        /**
         * Consumer对象在使用之前必须要调用start初始化,初始化一次即可
         */
        consumer.start();

        System.out.println("C1 Started.");
    }
}

  测试结果如下:

当"订单一号3"没有消费时 "订单一号4","订单一号5"是不能被消费的,"订单二号2"也是同样的情况。

(2). 并发消费

使用MessageListenerConcurrently,并发消费同一个队列中的数据,不能保证消费的顺序。

模拟在消费某个数据时出现了阻塞状态。

public class ConsumerConcurrently {
    public static void main(String[] args) throws InterruptedException,
            MQClientException {

        DefaultMQPushConsumer consumer = new DefaultMQPushConsumer("ConsumerGroupName");
        consumer.setNamesrvAddr("10.130.41.36:9876");
        consumer.setInstanceName("Consumer1");
        consumer.setMessageModel(MessageModel.CLUSTERING);

        consumer.subscribe("TopicTest", "*");
        consumer.registerMessageListener(new MessageListenerConcurrently() {
            @Override
            public ConsumeConcurrentlyStatus consumeMessage(List<MessageExt> msgs, ConsumeConcurrentlyContext context) {
                try {
                    for (MessageExt msg:msgs) {
                        String msgKey = msg.getKeys();
                        if(msgKey.equals("key13") || msgKey.equals("key22")){
                            Thread.sleep(1000);
                        }
                        System.out.println(" 消费者1 ==> 当前线程:"+Thread.currentThread().getName()+" ,quenuID: "+msg.getQueueId()+ " ,content: " + new String(msg.getBody()));
                    }
                } catch (Exception e) {
                    e.printStackTrace();
                    return ConsumeConcurrentlyStatus.RECONSUME_LATER;
                }

                //消费成功
                return ConsumeConcurrentlyStatus.CONSUME_SUCCESS;
            }
        });
        consumer.start();
        System.out.println("C1 Started.");
    }
}

  测试结果如下

当消费"订单一号3"阻塞时,会将后面的数据交给其他线程消费,所以"订单一号4" ,"订单一号5"在 "订单一号3"之前消费了。

(3). 集群消费

不同消费者设置成相同的组名,在MessageModel.CLUSTERING模式下,不同消费者会消费不同的队列,同一个消费者中保证顺序

消费者1

public class ConsumerOrderly_1 {
    public static void main(String[] args) throws InterruptedException,
            MQClientException {

        DefaultMQPushConsumer consumer = new DefaultMQPushConsumer("ConsumerGroupName");
        consumer.setNamesrvAddr("10.130.41.36:9876");
        consumer.setInstanceName("Consumer1");
        consumer.setMessageModel(MessageModel.CLUSTERING);
        consumer.subscribe("TopicTest", "*");

        consumer.registerMessageListener(new MessageListenerOrderly() {
            @Override
            public ConsumeOrderlyStatus consumeMessage(List<MessageExt> msgs, ConsumeOrderlyContext context) {
                //设置自动提交,如果不设置自动提交就算返回SUCCESS,消费者关闭重启 还是会重复消费的
                context.setAutoCommit(true);
                try {
                    for (MessageExt msg:msgs) {
                        String msgKey = msg.getKeys();
                        if(msgKey.equals("key13")){
                            Thread.sleep(1000);
                        }
                        System.out.println(" 消费者1 ==> 当前线程:"+Thread.currentThread().getName()+" ,quenuID: "+msg.getQueueId()+ " ,content: " + new String(msg.getBody()));
                    }
                } catch (Exception e) {
                    e.printStackTrace();
                    //如果出现异常,消费失败,挂起消费队列一会会,稍后继续消费
                    return ConsumeOrderlyStatus.SUSPEND_CURRENT_QUEUE_A_MOMENT;
                }

                //消费成功
                return ConsumeOrderlyStatus.SUCCESS;
            }
        });

        /**
         * Consumer对象在使用之前必须要调用start初始化,初始化一次即可
         */
        consumer.start();

        System.out.println("C1 Started.");
    }
}

 

消费者2

public class ConsumerOrderly_2 {
    public static void main(String[] args) throws InterruptedException,
            MQClientException {

        DefaultMQPushConsumer consumer = new DefaultMQPushConsumer("ConsumerGroupName");
        consumer.setNamesrvAddr("10.130.41.36:9876");
        consumer.setInstanceName("Consumer2");
        consumer.setMessageModel(MessageModel.CLUSTERING);
        consumer.subscribe("TopicTest", "*");

        consumer.registerMessageListener(new MessageListenerOrderly() {
            @Override
            public ConsumeOrderlyStatus consumeMessage(List<MessageExt> msgs, ConsumeOrderlyContext context) {
                //设置自动提交,如果不设置自动提交就算返回SUCCESS,消费者关闭重启 还是会重复消费的
                context.setAutoCommit(true);
                try {
                    for (MessageExt msg:msgs) {
                        String msgKey = msg.getKeys();
                        if(msgKey.equals("key22")){
                            Thread.sleep(1000);
                        }
                        System.out.println(" 消费者2 ==> 当前线程:"+Thread.currentThread().getName()+" ,quenuID: "+msg.getQueueId()+ " ,content: " + new String(msg.getBody()));
                    }
                } catch (Exception e) {
                    e.printStackTrace();
                    //如果出现异常,消费失败,挂起消费队列一会会,稍后继续消费
                    return ConsumeOrderlyStatus.SUSPEND_CURRENT_QUEUE_A_MOMENT;
                }

                //消费成功
                return ConsumeOrderlyStatus.SUCCESS;
            }
        });

        /**
         * Consumer对象在使用之前必须要调用start初始化,初始化一次即可
         */
        consumer.start();

        System.out.println("C2 Started.");
    }
}

测试结果如下:

消费者1负责队列1,并保证队列1中的所有消息是按照顺序消费的

消费者2负责队列2和队列3,根据"订单二号2"可以看出,他保证了队列2和队列3的顺序消费。

(4). 消费者A和消费者B同组,消费者A消费tagA,消费者B消费tagB如图

 在这种情况下,因为集群中订阅消息不一致,导致消费出现问题,最后启动的消费者才可以正常消费消息。

要解决这个问题,需要保证集群中的消费者拥?#22411;?#19968;的订阅消息,Topic和Tag要一致才可以。

参考:
https://www.jianshu.com/p/524ef06ce25a
https://mp.weixin.qq.com/s/HbIS0yEJsCPMYwwYDBIvMQ

(5). 消费者A和消费者B不同组,消费者A消费tagA,消费者B消费tagB

在消费者1中,能保证tagA1,tagA2顺序的消费,消费者2中能保证tagB1,tagB2顺序的消费。
但是不能保证tagA1和tagB1的消费顺序。

测试代码:

消费者1

public class ConsumerOrderly_1 {
    public static void main(String[] args) throws InterruptedException,
            MQClientException {

        DefaultMQPushConsumer consumer = new DefaultMQPushConsumer("ConsumerGroupName");
        consumer.setNamesrvAddr("10.130.41.36:9876");
        consumer.setInstanceName("Consumer1");
        consumer.setMessageModel(MessageModel.CLUSTERING);
        consumer.subscribe("TopicTest", "tagA");

        consumer.registerMessageListener(new MessageListenerOrderly() {
            @Override
            public ConsumeOrderlyStatus consumeMessage(List<MessageExt> msgs, ConsumeOrderlyContext context) {
                //设置自动提交,如果不设置自动提交就算返回SUCCESS,消费者关闭重启 还是会重复消费的
                context.setAutoCommit(true);
                try {
                    for (MessageExt msg:msgs) {
                        System.out.println(" 消费者1 ==> 当前线程:"+Thread.currentThread().getName()+" ,quenuID: "+msg.getQueueId()+ " ,content: " + new String(msg.getBody()));
                    }
                } catch (Exception e) {
                    e.printStackTrace();
                    //如果出现异常,消费失败,挂起消费队列一会会,稍后继续消费
                    return ConsumeOrderlyStatus.SUSPEND_CURRENT_QUEUE_A_MOMENT;
                }

                //消费成功
                return ConsumeOrderlyStatus.SUCCESS;
            }
        });

        /**
         * Consumer对象在使用之前必须要调用start初始化,初始化一次即可
         */
        consumer.start();

        System.out.println("C1 Started.");
    }
}

 

消费者2

public class ConsumerOrderly_2 {
    public static void main(String[] args) throws InterruptedException,
            MQClientException {

        DefaultMQPushConsumer consumer = new DefaultMQPushConsumer("ConsumerGroupName1");
        consumer.setNamesrvAddr("10.130.41.36:9876");
        consumer.setInstanceName("Consumer2");
        consumer.setMessageModel(MessageModel.CLUSTERING);
        consumer.subscribe("TopicTest", "tagB");

        consumer.registerMessageListener(new MessageListenerOrderly() {
            @Override
            public ConsumeOrderlyStatus consumeMessage(List<MessageExt> msgs, ConsumeOrderlyContext context) {
                //设置自动提交,如果不设置自动提交就算返回SUCCESS,消费者关闭重启 还是会重复消费的
                context.setAutoCommit(true);
                try {
                    for (MessageExt msg:msgs) {
                        String msgKey = msg.getKeys();
                        if(msgKey.equals("key11")){
                            Thread.sleep(1000);
                        }
                        System.out.println(" 消费者2 ==> 当前线程:"+Thread.currentThread().getName()+" ,quenuID: "+msg.getQueueId()+ " ,content: " + new String(msg.getBody()));
                    }
                } catch (Exception e) {
                    e.printStackTrace();
                    //如果出现异常,消费失败,挂起消费队列一会会,稍后继续消费
                    return ConsumeOrderlyStatus.SUSPEND_CURRENT_QUEUE_A_MOMENT;
                }

                //消费成功
                return ConsumeOrderlyStatus.SUCCESS;
            }
        });

        /**
         * Consumer对象在使用之前必须要调用start初始化,初始化一次即可
         */
        consumer.start();

        System.out.println("C2 Started.");
    }
}

 

测试结果:

消费者1

消费者2

"订单一号2" 在 "订单一号1" 前被消费了。



posted @ 2019-03-14 09:34 Sicwen 阅读(...) 评论(...) 编辑 收藏
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