rocketMq的消息的生产和消费

1、普通消息生产

        普通消息生产包括3种，可靠的同步传输、可靠的异步传输、单项传输。

       1)、可靠的同步传输

           说明：可靠的同步传输广泛应用于重要的通知消息、短信通知、短信营销系统等。

         示例代码：

         

DefaultMQProducer synProducer = new DefaultMQProducer("synProducerGroup");
synProducer.setNamesrvAddr("ip1:port;ip2:port");
synProducer.start();//启动服务
SendResult sendResult = synProducer.send(msg);//发送消息
synProducer.shutdown();//关闭资源

      2)、可靠的异步传输
          说明：可靠的异步传输通常应用于响应时间敏感的业务场景。
         示例代码：

        

DefaultMQProducer asynProducer = new DefaultMQProducer("asynProducerGroup");
asynProducer.setNamesrvAddr("ip1:port;ip2:port");
asynProducer.start();
asynProducer.send(msg, new CallSendback(){
    @Override
    public void onSuccess(SendResult sendResult){
        //消息发送成功
    }
    
    @Override
    public void onException(Trowable e){
        //消息发送异常
    }
});
asynProducer.shutdown();

       3）、单项传输
         说明：单项传输应用于中等可靠的情况下（即：对于数据可靠性要求不高），比如：日志收集。
        示例代码：       

      

DefaultMQProducer onewayProducer = new DefaultMQProducer("onewayProducerGroup");
onewayProducer.setNamesrvAddr("ip1:port;ip2:port");
onewayProducer.start();
onewayProducer.sendOneway(msg);
onewayProducer.shutdown();

  2、顺序消息
       说明：顺序消息通常应用于支付订单等对于消息顺序有严格要求的交易。
      示例代码：

    

生产者：
int orderId = 1000;//订单号

DefaultMQProducer orderProducer = new DefaultMQProducer("orderProducerGroup");
orderProducer.setNamesrvAddr("ip1:port;ip2:port");
orderProducer.start();
for(int i = 0; i < 10; i ++){
    Message msg = new Message("topic", "tags", "keys" + i, "body".getBytes(RemotingHelper.DEFAULT_CHARSET));
    orderProducer.send(msg, new MessageQueueSelector(){
    @Override
    public MessageQueue select(List mqs, Message msg, Object arg){
        Integer id = (Integer)arg;
        int index = id%mqs.size();
        return mqs.get(index);
    }
}, orderId);
}
orderProducer.shutdown();

消费者：

DefaultMQPushConsumer pushConsumer = new DefaultMQPushConsumer("pushConsumerGroup");
pushConsumer.setNamesrvAddr("ip1:port;ip2:port");
pushConsumer.subscribe("topic", "*");//订阅主题
pushConsumer.setConsumeFromWhere(ConsumeFromWhere.CONSUME_FROM_FIRST_OFFSET);
pushCosumer.setMessageModel(MessageModel.CLUSTERING);//集群消费、默认也是“集群消费”
pushConsumer.registerMessageListener(new MessageListenerOrderly(){
    @Override
    public ConsumeOrderStatus consumeMessage(List msgs, ConsumeOrderlyContext context){
        for(int i = 0; i < msgs.size(); i ++){
            Message msg = msgs.get(i);
            System.err.println("topic:" + msg.getTopic() + ",keys:" + msg.getKeys());
        }
        return ConsumeOrderStatus.SUCCESS;
    }
});
pushConsumer.start();

3、批量消息
      示例代码：
     

DefaultMQProducer batchProducer = new DefaultMQProducer("bathProducerGroup");
batchProducer.setNamesrvAddr("ip1:port;ip2:port");
batchProducer.start();
List msgs = new ArrayList();
msgs.add(msg1);
msgs.add(msg2);
..........
batchProducer.send(msgs);
batchProducer.shutdown();

4、延迟或定时消息
      说明：rocketMq目前只支持固定精度的定时消息，

官方说法如下：

如果要支持任意的时间精度，在 Broker 层面，必须要做消息排序，如果再涉及到持久化，那么消息排序要不可避免的产生巨大性能开销。

延迟级别：

延迟级别	时间
1	1s
2	5s
3	10s
4	30s
5	1m
6	2m
7	3m
8	4m
9	5m
10	6m
11	7m
12	8m
13	9m
14	10m
15	20m
16	30m
17	1h
18	2h

示例代码：

生产者：

DefaultMQProducer delayProducer = new DefaultMQProducer("delayProducerGroup");
delayProducer.setNamesrvAddr("ip1:port;ip2:port");
delayProducer.start();

Message delayMsg = new Message("topic", "tags" , "keys", "binary content");
delayMsg.setDelayTimeLevel(3);//延迟10s被消费
delayProducer.send(delayMsg);

delayProducer.shutdown();



消费者：

DefaultMQConsumer consume = new DefaultMQConsumer("consumeGroup");
consume.setNamesrvAddr("ip1:port;ip2:port");
consume.setConsumeFromWhere(ConsumeFromWhere.CONSUME_FROM_FIRST_OFFSET);
consume.registerMessageListener(new MessageListenerConcurrently(){
    @Override
    public ConsumeConcurrentlyStatus consumeMessage(List msgs, ConsumeConcurrentlyContext context){
        for(int i = 0; i < msgs.size(); i ++){
            Message msg = msgs.get(i);
            System.out.println("topic:" + msg.getTopic() + "keys:" + msg.getKeys());
        }
        return ConsumeConcurrentlyContext.CONSUME_SUCCESS;
    }
});

5、过滤消息

     说明：rocketMq提供了简单的消息过滤功能，仅支持一些简单的语法，

Grammars

RocketMQ only defines some basic grammars to support this feature. You could also extend it easily.

1. Numeric comparison, like >, >=, <, <=, BETWEEN, =;
2. Character comparison, like =, <>, IN;
3. IS NULL or IS NOT NULL;
4. Logical AND, OR, NOT;

Constant types are:

1. Numeric, like 123, 3.1415;
2. Character, like ‘abc’, must be made with single quotes;
3. NULL, special constant;
4. Boolean, TRUE or FALSE;

      示例代码：

   

生产者：

DefaultMQProducer producer = new DefaultMQProducer("filterGroup");
producer.setNamesrvAddr("ip1:port;ip2:port");
producer.start();

for(int i = 0; i < 10; i ++){
    Message msg = new Message("topic", "tags", "keys", "".getBytes());
    msg.putUserProperty("a", String.valueOf(i));
    producer.send(msg);
}

producer.shutdown();

消费者：

DefaultMQConsumer consumer = new DefaultMQConsumer("consumerFilterGroup");
consumer.setNamesrvAddr("ip1:port;ip2:port");
// only subsribe messages have property a, also a >=0 and a <= 3
consumer.subscribe("topic", MessageSelector.bySql("a between 1 and 5"));
consumer.registerMessageListener(new MessageListenerConcurrently(){
    @Override
    public ConsumeConcurrentlyStatus consumeMessage(List msgs, ConsumeConcurrentlyContext context){
        
        for(int i = 0; i < msgs.size(); i ++){
            //消费
        }
        
        return ConsumeConcurrentlyStatus.CONSUME_SUCCESS;
    }
});