• activemq学习笔记2


    基本步骤:

                ConnectionFactory factory = new ActiveMQConnectionFactory("tcp://127.0.0.1:61616");
                Connection connection = factory.createConnection();
                connection.start();
                Session session = connection.createSession(false, Session.AUTO_ACKNOWLEDGE);
                Destination que = new ActiveMQQueue("que");
                MessageProducer producer = session.createProducer(que);
                TextMessage msg = session.createTextMessage("hello activemq");
                producer.send(msg);
                //session.commit();
                session.close();
                connection.close();
    

    注意的地方

    1、连接开启
    connection.start();
    2.1、会话类型(事务型,非事务型)
    connection.createSession(false, Session.AUTO_ACKNOWLEDGE)的参数一
    2.2、应答模式
    connection.createSession(false, Session.AUTO_ACKNOWLEDGE)的参数二

        int AUTO_ACKNOWLEDGE = 1;
        int CLIENT_ACKNOWLEDGE = 2;
        int DUPS_OK_ACKNOWLEDGE = 3;
        int SESSION_TRANSACTED = 0;
    

    2.3、组合方式
    false:
    int AUTO_ACKNOWLEDGE = 1;
    int CLIENT_ACKNOWLEDGE = 2;
    int DUPS_OK_ACKNOWLEDGE = 3;
    true:
    int SESSION_TRANSACTED = 0;

    事务型需要session.commit()
    非事务型不能session.commit()

    持久化

    默认是持久化的,消息保存在磁盘,所以即使mq挂了,消息不会丢失

            <persistenceAdapter>
                <kahaDB directory="${activemq.data}/kahadb"/>
            </persistenceAdapter>
    

    配置持久化:

    producer.setDeliveryMode(DeliveryMode.PERSISTENT);
    
    public interface DeliveryMode {
        int NON_PERSISTENT = 1;
        int PERSISTENT = 2;
    }
    

    异步

    发送消息

                ActiveMQConnectionFactory factory = new ActiveMQConnectionFactory("tcp://127.0.0.1:61616");
                factory.setUseAsyncSend(true);
    

    非持久化消息模式下,默认就是异步发送过程,如果需要对非持久化消息的每次发送的消息都获得broker的回执的话

    connectionFactory.setAlwaysSyncSend()
    

    接受消息

    public class MsgReceiver {
        public static void main(String[] args) {
    
            try {
                ActiveMQConnectionFactory factory = new ActiveMQConnectionFactory("tcp://127.0.0.1:61616");
                Connection connection = factory.createConnection();
                connection.start();
                Session session = connection.createSession(false, Session.AUTO_ACKNOWLEDGE);
                Destination que = new ActiveMQQueue("que");
                MessageConsumer consumer = session.createConsumer(que);
                consumer.setMessageListener(new MsgListener());
                //session.commit();
                //session.close();
            } catch (JMSException e) {
                e.printStackTrace();
            }
        }
    }
    
    class MsgListener implements MessageListener {
    
        @Override
        public void onMessage(Message message) {
            TextMessage msg = (TextMessage) message;
            try {
                System.out.println(msg.getText());
            } catch (JMSException e) {
                e.printStackTrace();
            }
        }
    }
    

    异步接收不能提前关闭session,非事务不能commit()

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  • 原文地址:https://www.cnblogs.com/lanqie/p/8884250.html
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