Simple use of JMS-activemq

First, download activemq. the following link lists all versions:
Http://activemq.apache.org/download-archives.html
Each version provides links for different operating systems:

 

The company's computer is windows and started with activemq. bat in the directory:

 

The default port number is 61616, which can be seen in CONF/activemq. xml:

<transportConnectors>    <!-- DOS protection, limit concurrent connections to 1000 and frame size to 100MB -->    <transportConnector name="openwire" uri="tcp://0.0.0.0:61616?maximumConnections=1000&amp;wireFormat.maxFrameSize=104857600"/>    <transportConnector name="amqp" uri="amqp://0.0.0.0:5672?maximumConnections=1000&amp;wireFormat.maxFrameSize=104857600"/>    <transportConnector name="stomp" uri="stomp://0.0.0.0:61613?maximumConnections=1000&amp;wireFormat.maxFrameSize=104857600"/>    <transportConnector name="mqtt" uri="mqtt://0.0.0.0:1883?maximumConnections=1000&amp;wireFormat.maxFrameSize=104857600"/>    <transportConnector name="ws" uri="ws://0.0.0.0:61614?maximumConnections=1000&amp;wireFormat.maxFrameSize=104857600"/></transportConnectors>

 

Related Maven dependency:

<dependency>    <groupId>javax.jms</groupId>    <artifactId>javax.jms-api</artifactId>    <version>2.0</version></dependency><dependency>    <groupId>org.apache.activemq</groupId>    <artifactId>activemq-core</artifactId>    <version>5.7.0</version></dependency>

 

Use javax. JMS. Session to communicate with the JMS provider:

ConnectionFactory connectionFactory = new ActiveMQConnectionFactory(        ActiveMQConnection.DEFAULT_USER,        ActiveMQConnection.DEFAULT_PASSWORD, "tcp://localhost:61616");                                                                                                                                                Connection connection = connectionFactory.createConnection();connection.start();                                                                                                                                                Session session = connection.createSession(Boolean.TRUE,        Session.AUTO_ACKNOWLEDGE);

 

Then some destinations, senders, and sent content are all made by the session:

Destination = session. createqueue ("this is Sparta !! "); Messageproducer producer = session. createproducer (destination); textmessage message0 = session. createtextmessage (" this is Sparta !!! "); Textmessage message1 = session. createtextmessage (" this is also Sparta !!! "); Textmessage message2 = session. createtextmessage (" These are all Sparta !!! "); Producer. Send (message0); producer. Send (message1); producer. Send (message2); Session. Commit ();

 

With producer, consumer is also available. The method for receiving messages is as follows:

MessageConsumer consumer = session.createConsumer(destination);System.out.println(((TextMessage) consumer.receive(10000)).getText());

 

The result is that the consumer goes to the receive one by one, just as the recipient confirms it in person.
Maybe we can let listener do the following:

consumer.setMessageListener(new MessageListener() {    public void onMessage(Message message) {        try {            System.out.println("listener catched:::"+((TextMessage)message).getText());        } catch (JMSException e) {            e.printStackTrace();        }    }});

 

When this consumer is set to listener, it cannot be received in the receive () method,
Otherwise, javax. JMS. illegalstateexception: cannot synchronously receive a message when a messagelistener is set

If you want to use publish/subscribe, simply change createqueue to createtopic, but you must understand that the topic is stateless.

The complete code is as follows, Sender:

{Connectionfactory = new activemqconnectionfactory (activemqconnection. default_user, activemqconnection. default_password, "TCP: // localhost: 61616"); connection = connectionfactory. createconnection (); connection. start (); Session session = connection. createsession (Boolean. true, session. auto_acknowledge); destination Destination = session. createqueue ("this is Sparta !! "); Messageproducer producer = session. createproducer (destination); textmessage message0 = session. createtextmessage (" this is Sparta !!! "); Textmessage message1 = session. createtextmessage (" this is also Sparta !!! "); Textmessage message2 = session. createtextmessage (" These are all Sparta !!! "); Producer. Send (message0); producer. Send (message1); producer. Send (message2); Session. Commit ();}

 

Recipient:

{        ConnectionFactory connectionFactory = new ActiveMQConnectionFactory(                ActiveMQConnection.DEFAULT_USER,                ActiveMQConnection.DEFAULT_PASSWORD, "tcp://localhost:61616");;        Connection connection = connectionFactory.createConnection();        connection.start();                                                                                                                                                                                                                                                                Session session = connection.createSession(Boolean.FALSE,                Session.AUTO_ACKNOWLEDGE);                                                                                                                                                                                                                                                                Destination destination = session.createQueue("this is sparta!!");        MessageConsumer consumer = session.createConsumer(destination);        System.out.println(((TextMessage) consumer.receive(10000)).getText());        System.out.println(((TextMessage) consumer.receive(10000)).getText());        System.out.println(((TextMessage) consumer.receive(10000)).getText());    }

 

Simple use of JMS-activemq