Example code

Example code is from here with some modification. As of writing Spring Boot 3.3.0 (Spring Framework 6.1.8) is used.

complete/pom.xml

Switch to ActiveMQ embedded broker

<dependency>
    <groupId>org.springframework.boot</groupId>
    <!--<artifactId>spring-boot-starter-artemis</artifactId>-->
    <artifactId>spring-boot-starter-activemq</artifactId>
</dependency>

<dependency>
    <groupId>org.apache.activemq</groupId>
    <!--<artifactId>artemis-jakarta-server</artifactId>-->
    <artifactId>activemq-broker</artifactId>
    <scope>runtime</scope>
</dependency>

<!-- ... -->

complete/src/main/resources/application.properties

Switch on debug logging and setup embedded broker url

#spring.artemis.mode=embedded
debug=true
spring.activemq.broker-url=vm://localhost?broker.persistent=false

complete/src/main/java/hello/Application.java

Use JmsListenerContainerFactory bean created by Spring Boot rather than build by our own

@SpringBootApplication
@EnableJms
public class Application {

    /*@Bean
    public JmsListenerContainerFactory<?> myFactory(ConnectionFactory connectionFactory,
                                                    DefaultJmsListenerContainerFactoryConfigurer configurer) {
        DefaultJmsListenerContainerFactory factory = new DefaultJmsListenerContainerFactory();
        // This provides all auto-configured defaults to this factory, including the message converter
        configurer.configure(factory, connectionFactory);
        // You could still override some settings if necessary.
        return factory;
    }*/

    //...

}

complete/src/main/java/hello/Receiver.java

Specify default JmsListenerContainerFactory

@Component
public class Receiver {

    //@JmsListener(destination = "mailbox", containerFactory = "myFactory")
    @JmsListener(destination = "mailbox")
    public void receiveMessage(Email email) {
        System.out.println("Received <" + email + ">");
    }

}

Spring Boot auto configuration log

Only JMS related configuration is shown.

   ActiveMQAutoConfiguration matched:
      - @ConditionalOnClass found required classes 'jakarta.jms.ConnectionFactory', 'org.apache.activemq.ActiveMQConnectionFactory' (OnClassCondition)
      - @ConditionalOnMissingBean (types: jakarta.jms.ConnectionFactory; SearchStrategy: all) did not find any beans (OnBeanCondition)

   ActiveMQAutoConfiguration#activemqConnectionDetails matched:
      - @ConditionalOnMissingBean (types: org.springframework.boot.autoconfigure.jms.activemq.ActiveMQConnectionDetails; SearchStrategy: all) did not find any beans (OnBeanCondition)

   ActiveMQConnectionFactoryConfiguration matched:
      - @ConditionalOnMissingBean (types: jakarta.jms.ConnectionFactory; SearchStrategy: all) did not find any beans (OnBeanCondition)

   ActiveMQConnectionFactoryConfiguration.SimpleConnectionFactoryConfiguration matched:
      - @ConditionalOnProperty (spring.activemq.pool.enabled=false) matched (OnPropertyCondition)

   ActiveMQConnectionFactoryConfiguration.SimpleConnectionFactoryConfiguration.CachingConnectionFactoryConfiguration matched:
      - @ConditionalOnClass found required class 'org.springframework.jms.connection.CachingConnectionFactory' (OnClassCondition)
      - @ConditionalOnProperty (spring.jms.cache.enabled=true) matched (OnPropertyCondition)

   JmsAnnotationDrivenConfiguration matched:
      - @ConditionalOnClass found required class 'org.springframework.jms.annotation.EnableJms' (OnClassCondition)

   JmsAnnotationDrivenConfiguration#jmsListenerContainerFactory matched:
      - @ConditionalOnSingleCandidate (types: jakarta.jms.ConnectionFactory; SearchStrategy: all) found a single bean 'jmsConnectionFactory'; @ConditionalOnMissingBean (names: jmsListenerContainerFactory; SearchStrategy: all) did not find any beans (OnBeanCondition)

   JmsAnnotationDrivenConfiguration#jmsListenerContainerFactoryConfigurer matched:
      - @ConditionalOnMissingBean (types: org.springframework.boot.autoconfigure.jms.DefaultJmsListenerContainerFactoryConfigurer; SearchStrategy: all) did not find any beans (OnBeanCondition)

   JmsAutoConfiguration matched:
      - @ConditionalOnClass found required classes 'jakarta.jms.Message', 'org.springframework.jms.core.JmsTemplate' (OnClassCondition)
      - @ConditionalOnBean (types: jakarta.jms.ConnectionFactory; SearchStrategy: all) found bean 'jmsConnectionFactory' (OnBeanCondition)

   JmsAutoConfiguration.JmsTemplateConfiguration#jmsTemplate matched:
      - @ConditionalOnSingleCandidate (types: jakarta.jms.ConnectionFactory; SearchStrategy: all) found a single bean 'jmsConnectionFactory'; @ConditionalOnMissingBean (types: org.springframework.jms.core.JmsOperations; SearchStrategy: all) did not find any beans (OnBeanCondition)

   JmsAutoConfiguration.MessagingTemplateConfiguration matched:
      - @ConditionalOnClass found required class 'org.springframework.jms.core.JmsMessagingTemplate' (OnClassCondition)

   JmsAutoConfiguration.MessagingTemplateConfiguration#jmsMessagingTemplate matched:
      - @ConditionalOnSingleCandidate (types: org.springframework.jms.core.JmsTemplate; SearchStrategy: all) found a single bean 'jmsTemplate'; @ConditionalOnMissingBean (types: org.springframework.jms.core.JmsMessageOperations; SearchStrategy: all) did not find any beans (OnBeanCondition)

Related interface

About ConnectionFactory

The implementation of ActiveMQ is org.apache.activemq.ActiveMQConnectionFactory, but Spring Framework does not use it directly. The class is wrapped by org.springframework.jms.connection.CachingConnectionFactory for following

• only one Connection is created and this will be reused
• cache MessageProducer and MessageConsumer (In this example only MessageProducer is cached)

Publisher

Sending message through org.springframework.jms.core.JmsTemplate

<dependency>
    <groupId>org.springframework.boot</groupId>
    <!--<artifactId>spring-boot-starter-artemis</artifactId>-->
    <artifactId>spring-boot-starter-activemq</artifactId>
</dependency>

<dependency>
    <groupId>org.apache.activemq</groupId>
    <!--<artifactId>artemis-jakarta-server</artifactId>-->
    <artifactId>activemq-broker</artifactId>
    <scope>runtime</scope>
</dependency>

<!-- ... -->

JmsTemplate bean is built by org.springframework.boot.autoconfigure.jms.JmsAutoConfiguration.JmsTemplateConfiguration#jmsTemplate. A MessageConverter bean is necessary for deserializing the DTO.

DestinationResolver used is org.springframework.jms.support.destination.DynamicDestinationResolver, the class is just get jakarta.jms.Destination instance by calling jakarta.jms.Session#createTopic or jakarta.jms.Session#createQueue.

Subscriber

org.springframework.jms.annotation.JmsListener annotation

org.springframework.jms.listener.DefaultMessageListenerContainer class

In JMS specification, asynchronous message processing is supported and the listener is running under threads of the JMS provider.

<dependency>
    <groupId>org.springframework.boot</groupId>
    <!--<artifactId>spring-boot-starter-artemis</artifactId>-->
    <artifactId>spring-boot-starter-activemq</artifactId>
</dependency>

<dependency>
    <groupId>org.apache.activemq</groupId>
    <!--<artifactId>artemis-jakarta-server</artifactId>-->
    <artifactId>activemq-broker</artifactId>
    <scope>runtime</scope>
</dependency>

<!-- ... -->

But asynchronous approaches are not used in Spring Framework, synchronous API (polling) is used. The actual code is in org.springframework.jms.support.destination.JmsDestinationAccessor#receiveFromConsumer.

#spring.artemis.mode=embedded
debug=true
spring.activemq.broker-url=vm://localhost?broker.persistent=false

org.springframework.jms.listener.DefaultMessageListenerContainer.AsyncMessageListenerInvoker class is for performing periodically poll jobs. This is scheduled in org.springframework.core.task.SimpleAsyncTaskExecutor.

One DefaultMessageListenerContainer instance is created for one @JmsListener annotated function. This is produced by org.springframework.jms.config.DefaultJmsListenerContainerFactory.

Of course MessageConverter and ExceptionListener instance are necessary.

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