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Salad Lam
Salad Lam

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Quick look on how Spring Boot supports JMS

#java #springboot

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> <!-- ... -->
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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
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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; }*/ //... }
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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 + ">"); } }
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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)
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Related interface

Interface Function
org.springframework.jms.support.destination.DestinationResolver lookup jakarta.jms.Destination instance by String name
org.springframework.transaction.jta.JtaTransactionManager control transaction by JTA
org.springframework.jms.support.converter.MessageConverter serialize/deserialize DTO instance
jakarta.jms.ExceptionListener processor when jakarta.jms.JMSException throws. One implementation is SingleConnectionFactory, connection managed by that class will be restarted once exception is catched
io.micrometer.observation.ObservationRegistry for statistics

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

jmsTemplate.convertAndSend("mailbox", new Email("info@example.com", "Hello"));
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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

attribute Function
id prefix of thread name which run listener
containerFactory bean name of JmsListenerContainerFactory instance
destination the destination name for this listener
subscription the name of the durable subscription, if any
selector an optional message selector for this listener
concurrency number of thread running listener

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.

MessageConsumer consumer; MessageListener listener = new MyListener(); consumer.setMessageListener(listener);
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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.

@Nullable protected Message receiveFromConsumer(MessageConsumer consumer, long timeout) throws JMSException { if (timeout > 0) { return consumer.receive(timeout); } else if (timeout < 0) { return consumer.receiveNoWait(); } else { return consumer.receive(); } }
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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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