【RocketMQ】RocketMQ事务消息 Demo

<dependencies>
<!-- RocketMQ -->
<dependency> 
<groupId>org.apache.rocketmq</groupId> 
<artifactId>rocketmq-all</artifactId> 
<version>4.3.0</version> 
<type>pom</type> 
</dependency>
<dependency> 
<groupId>org.apache.rocketmq</groupId> 
<artifactId>rocketmq-client</artifactId> 
<version>4.3.0</version> 
</dependency>

<dependency>
<groupId>ch.qos.logback</groupId>
<artifactId>logback-classic</artifactId>
<version>1.1.1</version>
</dependency>

<dependency>
<groupId>ch.qos.logback</groupId>
<artifactId>logback-core</artifactId>
<version>1.1.1</version>
</dependency>
</dependencies>

package cn.ebiz.rocketmq.transaction;
import org.apache.rocketmq.client.exception.MQClientException;
import org.apache.rocketmq.client.producer.LocalTransactionState;
import org.apache.rocketmq.client.producer.SendResult;
import org.apache.rocketmq.client.producer.TransactionListener;
import org.apache.rocketmq.client.producer.TransactionMQProducer;
import org.apache.rocketmq.common.message.Message;
import org.apache.rocketmq.common.message.MessageExt;
public class Producer {
　　public static void main(String[] args) throws MQClientException, InterruptedException {
　　//01 new 一个有事务基因的生产者
　　TransactionMQProducer producer = new TransactionMQProducer("ProducerGroup");
　　//02 注册
　　producer.setNamesrvAddr("127.0.0.1:9876");
　　//03 开启
　　producer.start();
/**
 * 04 生产者设置事务监听器，匿名内部类new一个事务监听器，
 * 重写“执行本地事务”和“检查本地事务”两个方法，返回值都为
 * “本地事务状态”
 */
　　producer.setTransactionListener(new TransactionListener() {
　　　　　　　　　public LocalTransactionState executeLocalTransaction(Message msg, Object arg) {
　　　　　　　　　　　　　　String tag = msg.getTags();
                　　　　if(tag.equals("Transaction1")) {
                   　　　　 System.out.println("这里处理业务逻辑,比如操作数据库，失败情况下进行回滚");
                    　　　　//如果失败，再次给MQ发送消息
                    　　　　return LocalTransactionState.ROLLBACK_MESSAGE;
                　　　　}
                　　return LocalTransactionState.COMMIT_MESSAGE;
           　　 }

           　　 public LocalTransactionState checkLocalTransaction(MessageExt msg) {
                　　System.out.println("state -- "+new String(msg.getBody()));
                　　return LocalTransactionState.COMMIT_MESSAGE;
           　　 }
        　　});

   for(int i=0;i<2;i++) {
            try {
        　　　　　// 05 准备要发送的message，名字，标签，内容
                Message msg = new Message("TopicTransaction","Transaction" + i,("Hello RocketMQ "+i).getBytes("UTF-8"));
       　　　　　 // 06 用发送事务特有的方法发送消息，而不是简单的producer.send(msg);
                SendResult sendResult = producer.sendMessageInTransaction(msg, null);
                System.out.println(msg.getBody());
            } catch (Exception e) {
                e.printStackTrace();
                Thread.sleep(1000);
            }
   }
        // 07 关闭
        producer.shutdown();
    }
}

package cn.ebiz.rocketmq.transaction;
import java.util.List;
import org.apache.rocketmq.client.consumer.DefaultMQPushConsumer;
import org.apache.rocketmq.client.consumer.listener.ConsumeConcurrentlyContext;
import org.apache.rocketmq.client.consumer.listener.ConsumeConcurrentlyStatus;
import org.apache.rocketmq.client.consumer.listener.MessageListenerConcurrently;
import org.apache.rocketmq.client.exception.MQClientException;
import org.apache.rocketmq.common.consumer.ConsumeFromWhere;
import org.apache.rocketmq.common.message.MessageExt;
public class Consumer0 {
        public static void main(String[] args) throws MQClientException {
　　　　　　　　//01默认的消息消费FF者
            DefaultMQPushConsumer consumer = new DefaultMQPushConsumer("ConsumerGroup");
　　　　　　　　//02注册
            consumer.setNamesrvAddr("127.0.0.1:9876");
　　　　　　　　//03设置获取原则
            consumer.setConsumeFromWhere(ConsumeFromWhere.CONSUME_FROM_FIRST_OFFSET);
　　　　　　　　//04订阅
            consumer.subscribe("TopicTransaction","*");
　　　　　　　　//05注册监听器
            consumer.registerMessageListener(new MessageListenerConcurrently() {
                public ConsumeConcurrentlyStatus consumeMessage(List<MessageExt> msgs,
                                                                ConsumeConcurrentlyContext context) {
                    try {
　　　　　　　　// 06接收消息并打印
                        for (MessageExt msg : msgs) {
                            String topic = msg.getTopic();
                            String msgBody = new String(msg.getBody(),"utf-8");
                            String tags = msg.getTags();
                            System.out.println("收到消息： topic:"+topic+" ,tags:"+tags+" ,msg: "+msgBody);
                        }
                    } catch (Exception e) {
                        e.printStackTrace();
　　　　　　　　// 1s 2s 5s ... 2h
                        return ConsumeConcurrentlyStatus.RECONSUME_LATER;
                    }
                    return ConsumeConcurrentlyStatus.CONSUME_SUCCESS;
                }
            });
　　　　　　　　// 07开启
            consumer.start();
            System.out.println("Consumer Started.");
        }
    }