ActiveMQ消息的延时和定时投递

ActiveMQ对消息延时和定时投递做了很好的支持，其内部启动Scheduled来对该功能支持，也提供了一个封装的消息类型：org.apache.activemq.ScheduledMessage，只需要把几个描述消息定时调度方式的参数作为属性添加到消息，broker端的调度器就会按照我们想要的行为去处理消息。

Property name	type	description
AMQ_SCHEDULED_DELAY	long	延迟投递的时间
AMQ_SCHEDULED_PERIOD	long	重复投递的时间间隔
AMQ_SCHEDULED_REPEAT	int	重复投递次数
AMQ_SCHEDULED_CRON	String	Cron表达式

下面我们演示一下间隔性重复投递；

生产者：

package cn.slimsmart.study.activemq;
 
import javax.jms.Connection;
import javax.jms.ConnectionFactory;
import javax.jms.DeliveryMode;
import javax.jms.Destination;
import javax.jms.MessageProducer;
import javax.jms.Session;
import javax.jms.TextMessage;
 
import org.apache.activemq.ActiveMQConnection;
import org.apache.activemq.ActiveMQConnectionFactory;
import org.apache.activemq.ScheduledMessage;
 
public class Producer {
 
    public static final String broker_url = "failover:(tcp://10.1.199.169:61616)";
    private static String queue_name = "test.queue";
 
    public static void main(String[] args) throws Exception {
        ConnectionFactory factory = new ActiveMQConnectionFactory(ActiveMQConnection.DEFAULT_USER, ActiveMQConnection.DEFAULT_PASSWORD, broker_url);
        // 通过工厂创建一个连接
        Connection connection = factory.createConnection();
        // 启动连接
        connection.start();
        // 创建一个session会话 事务 自动ack
        Session session = connection.createSession(Boolean.TRUE, Session.AUTO_ACKNOWLEDGE);
        // 创建一个消息队列
        Destination destination = session.createQueue(queue_name);
        // 创建生产者
        MessageProducer producer = session.createProducer(destination);
        // 消息持久化
        producer.setDeliveryMode(DeliveryMode.PERSISTENT);
        TextMessage message = session.createTextMessage("test delay message:" + System.currentTimeMillis());
        long time = 60 * 1000;// 延时1min
        long period = 10 * 1000;// 每个10s
        int repeat = 6;// 6次
        message.setLongProperty(ScheduledMessage.AMQ_SCHEDULED_DELAY, time);
        message.setLongProperty(ScheduledMessage.AMQ_SCHEDULED_PERIOD, period);
        message.setIntProperty(ScheduledMessage.AMQ_SCHEDULED_REPEAT, repeat);
        // 发送消息
        producer.send(message);
        session.commit();
        producer.close();
        session.close();
        connection.close();
    }
}

消费者代码：

package cn.slimsmart.study.activemq;
 
import java.util.concurrent.CountDownLatch;
 
import javax.jms.Connection;
import javax.jms.ConnectionFactory;
import javax.jms.Destination;
import javax.jms.JMSException;
import javax.jms.Message;
import javax.jms.MessageConsumer;
import javax.jms.MessageListener;
import javax.jms.Session;
import javax.jms.TextMessage;
 
import org.apache.activemq.ActiveMQConnection;
import org.apache.activemq.ActiveMQConnectionFactory;
 
public class Consumer {
 
    public static final String broker_url = "failover:(tcp://10.1.199.169:61616)";
    private static String queue_name = "test.queue";
 
    public static void main(String[] args) throws Exception {
        ConnectionFactory factory = new ActiveMQConnectionFactory(ActiveMQConnection.DEFAULT_USER, ActiveMQConnection.DEFAULT_PASSWORD, broker_url);
        // 通过工厂创建一个连接
        Connection connection = factory.createConnection();
        // 启动连接
        connection.start();
        // 创建一个session会话 事务 自动ack
        Session session = connection.createSession(Boolean.TRUE, Session.CLIENT_ACKNOWLEDGE);
        // 创建一个消息队列
        Destination destination = session.createQueue(queue_name);
        // 创建消费者
        MessageConsumer consumer = session.createConsumer(destination);
        consumer.setMessageListener(new MessageListener() {
            @Override
            public void onMessage(Message message) {
                try {
                    System.out.println("receive message ：" + ((TextMessage) message).getText());
                    message.acknowledge();
                } catch (JMSException e) {
                    e.printStackTrace();
                }
            }
        });
        new CountDownLatch(1).await();
    }
}