Two modes: queue mode / topic mode

pom.xml

<dependency>
        <groupId>org.apache.activemq</groupId>
        <artifactId>activemq-all</artifactId>
        <version>5.15.9</version>
</dependency>  

In fact, the queuing mode is the food sharing mode.

For example, if the manufacturer sends 10 messages to the activeMQ server, and there are multiple consumers at this time, these consumers will divide these 10 messages, and only one consumer will get one message.
Theme mode is subscription mode.

For example, the producer has sent 10 messages, and at this time there are multiple consumers, so many consumers can get these 10 messages, just like subscribing to the public number.

Queue mode:

1. Run the TestConsumer class twice to start two different consumers
2. Run TestProducer once to start the producer

Producers produce 100, and two consumers divide up

Consumer:

public class TestConsumer {
    //Service address, port default 61616
    private static final String url="tcp://127.0.0.1:61616";
    //Message name of this consumption
    private static final String topicName="queue_style";

    //There may be multiple consumers. In order to distinguish different consumers, create random names for them
    private static final String consumerName="consumer-" + RandomUtil.randomString(5);
    public static void main(String[] args) throws JMSException {
        //0. First, judge whether the port is started Active MQ The server
        ActiveMQUtil.checkServer();
        System.out.printf("%s Consumer started. %n", consumerName);

        //1.Establish ConnectiongFactory,Binding address
        ConnectionFactory factory=new ActiveMQConnectionFactory(url);
        //2.Establish Connection
        Connection connection= factory.createConnection();
        //3.Start connection
        connection.start();
        //4.Create session
        Session session=connection.createSession(false, Session.AUTO_ACKNOWLEDGE);
        //5.Create a target (topic type)
        Destination destination=session.createQueue(topicName);
        //6.Create a consumer
        MessageConsumer consumer=session.createConsumer(destination);
        //7.Create a listener
        consumer.setMessageListener(new MessageListener() {

            public void onMessage(Message arg0) {
                // TODO Auto-generated method stub
                TextMessage textMessage=(TextMessage)arg0;
                try {
                    System.out.println(consumerName +" Receive message:"+textMessage.getText());
                } catch (JMSException e) {
                    // TODO Auto-generated catch block
                    e.printStackTrace();
                }

            }
        });
        
        //8. I don't know when it will be, so I can't shut it down. I'm not shutting it down. I've been monitoring it
        //connection.close();
    }
}

Producer:

public class TestProducer {

    //Service address, port default 61616
    private static final String url="tcp://127.0.0.1:61616";
    //The name of the message sent this time
    private static final String topicName="queue_style";
    public static void main(String[] args) throws JMSException {
        //0. First, judge whether the port is started  Active MQ The server
        ActiveMQUtil.checkServer();
        //1.Establish ConnectiongFactory,Binding address
        ConnectionFactory factory=new ActiveMQConnectionFactory(url);
        //2.Establish Connection
        Connection connection= factory.createConnection();
        //3.Start connection
        connection.start();
        //4.Create session
        Session session=connection.createSession(false, Session.AUTO_ACKNOWLEDGE);
        //5.Create a goal (Queue type)
        Destination destination=session.createQueue(topicName);
        //6.Create a producer
        MessageProducer producer=session.createProducer(destination);


        for (int i = 0; i < 100; i++) {
            //7.Create message
            TextMessage textMessage=session.createTextMessage("Queue message-"+i);
            //8.send message
            producer.send(textMessage);
            System.out.println("Send out:"+textMessage.getText());
        }
        //7. Close connection
        connection.close();
    }
}

2 consumer s:

Producer production:

Theme mode:

Consumer, producer

public class TestConsumer {
    //Service address, port default 61616
    private static final String url="tcp://127.0.0.1:61616";
    //Message name of this consumption
    private static final String topicName="topic_style";

    //There may be multiple consumers. In order to distinguish different consumers, create random names for them
    private static final String consumerName="consumer-" + RandomUtil.randomString(5);
    public static void main(String[] args) throws JMSException {
        

        //0. First, judge whether the port is started Active MQ The server
        ActiveMQUtil.checkServer();
        System.out.printf("%s Consumer started. %n", consumerName);
        //1.Establish ConnectiongFactory,Binding address
        ConnectionFactory factory=new ActiveMQConnectionFactory(url);
        //2.Establish Connection
        Connection connection= factory.createConnection();
        //3.Start connection
        connection.start();
        //4.Create session
        Session session=connection.createSession(false, Session.AUTO_ACKNOWLEDGE);

        //5.Create a target (topic type)
        Destination destination=session.createTopic(topicName);

        //6.Create a consumer
        MessageConsumer consumer=session.createConsumer(destination);
        //7.Create a listener
        consumer.setMessageListener(new MessageListener() {

            public void onMessage(Message arg0) {
                // TODO Auto-generated method stub
                TextMessage textMessage=(TextMessage)arg0;
                try {
                    System.out.println(consumerName +" Receive message:"+textMessage.getText());
                } catch (JMSException e) {
                    // TODO Auto-generated catch block
                    e.printStackTrace();
                }

            }
        });
        
        //8. I don't know when it will be, so I can't shut it down. I'm not shutting it down. I've been monitoring it
        //connection.close();
    }
}

public class TestProducer {

    //Service address, port default 61616
    private static final String url="tcp://127.0.0.1:61616";
    //The name of the message sent this time
    private static final String topicName="topic_style";
    public static void main(String[] args) throws JMSException {
        //0. First, judge whether the port is started  Active MQ The server
        ActiveMQUtil.checkServer();
        //1.Establish ConnectiongFactory,Binding address
        ConnectionFactory factory=new ActiveMQConnectionFactory(url);
        //2.Establish Connection
        Connection connection= factory.createConnection();
        //3.Start connection
        connection.start();
        //4.Create session
        Session session=connection.createSession(false, Session.AUTO_ACKNOWLEDGE);
        //5.Create a goal (Topic type)
        Destination destination=session.createTopic(topicName);
        //6.Create a producer
        MessageProducer producer=session.createProducer(destination);


        for (int i = 0; i < 100; i++) {
            //7.Create message
            TextMessage textMessage=session.createTextMessage("Topic message-"+i);
            //8.send message
            producer.send(textMessage);
            System.out.println("Send out:"+textMessage.getText());
        }
        //7. Close connection
        connection.close();
    }
}

Producers produce 100, and both consumers accept 100