dev-resources.site
for different kinds of informations.
Using multiple JMS servers with Spring Boot
Spring Boot support for JMS is straightforward to use. But the default configuration is limited to one server.
Let's see how to use more than one server. (In this example I will be using IBM MQ, but the same principle can be applied to other products.)
First we need to add configuration properties for two servers:
qm1.queueManager=QM1
qm1.channel=DEV.ADMIN.SVRCONN
qm1.connName=localhost(1414)
qm1.user=admin
qm1.password=passw0rd
qm1.pool.enabled=true
qm2.queueManager=QM2
qm2.channel=DEV.ADMIN.SVRCONN
qm2.connName=localhost(1415)
qm2.user=admin
qm2.password=passw0rd
qm2.pool.enabled=true
In this example we added the "qm1" and "qm2" prefixes to the standard properties, to configure the two servers.
For each one of the servers we need to read these properties (using @ConfigurationProperties annotation with the prefix) and create an specific ConnectionFactory and JmsListenerContainerFactory.
The Qm1Config and Qm2Config configure these beans.
@Configuration
public class Qm1Config {
@Bean
@ConfigurationProperties("qm1")
public MQConfigurationProperties qm1ConfigProperties() {
return new MQConfigurationProperties();
}
@Bean
public MQConnectionFactory qm1ConnectionFactory(@Qualifier("qm1ConfigProperties") MQConfigurationProperties properties, ObjectProvider<List<MQConnectionFactoryCustomizer>> factoryCustomizers) {
return new MQConnectionFactoryFactory(properties, factoryCustomizers.getIfAvailable()).createConnectionFactory(MQConnectionFactory.class);
}
@Bean
public JmsListenerContainerFactory<?> qm1JmsListenerContainerFactory(@Qualifier("qm1ConnectionFactory") ConnectionFactory connectionFactory, DefaultJmsListenerContainerFactoryConfigurer configurer) {
DefaultJmsListenerContainerFactory factory = new DefaultJmsListenerContainerFactory();
configurer.configure(factory, connectionFactory);
return factory;
}
}
@Configuration
public class Qm2Config {
@Bean
@ConfigurationProperties("qm2")
public MQConfigurationProperties qm2ConfigProperties() {
return new MQConfigurationProperties();
}
@Bean
public MQConnectionFactory qm2ConnectionFactory(@Qualifier("qm2ConfigProperties") MQConfigurationProperties properties, ObjectProvider<List<MQConnectionFactoryCustomizer>> factoryCustomizers) {
return new MQConnectionFactoryFactory(properties, factoryCustomizers.getIfAvailable()).createConnectionFactory(MQConnectionFactory.class);
}
@Bean
public JmsListenerContainerFactory<?> qm2JmsListenerContainerFactory(@Qualifier("qm2ConnectionFactory") ConnectionFactory connectionFactory, DefaultJmsListenerContainerFactoryConfigurer configurer) {
DefaultJmsListenerContainerFactory factory = new DefaultJmsListenerContainerFactory();
configurer.configure(factory, connectionFactory);
return factory;
}
}
Then, the listener must specify which queue manager is to be used:
@Component
public class QueueConsumer {
@JmsListener(destination = "${example.queue}", containerFactory = "qm1JmsListenerContainerFactory")
public void receive1(String text) {
System.out.println("Received from qm1: " + text);
}
@JmsListener(destination = "${example.queue}", containerFactory = "qm2JmsListenerContainerFactory")
public void receive2(String text) {
System.out.println("Received from qm2: " + text);
}
}
And that's it!
Example
A complete runnable example is available in GitHub:
https://github.com/adzubla/qmgrs
Dynamic creation of listeners
The above solution hardwires the JmsListeners and ConnectionFactories in source code. To have a configurable number of queue managers we can use the approach that follows.
The new properties file:
qm.list.0.queueManager=QM1
qm.list.0.channel=DEV.ADMIN.SVRCONN
qm.list.0.connName=localhost(1414)
qm.list.0.user=admin
qm.list.0.password=passw0rd
qm.list.0.pool.enabled=true
qm.list.1.queueManager=QM2
qm.list.1.channel=DEV.ADMIN.SVRCONN
qm.list.1.connName=localhost(1415)
qm.list.1.user=admin
qm.list.1.password=passw0rd
qm.list.1.pool.enabled=true
To read these properties in a List of properties, we use the configuration below:
@ConfigurationProperties("qm")
@Configuration
public class QmProperties {
private List<MQConfigurationProperties> list;
public List<MQConfigurationProperties> getList() {
return list;
}
public void setList(List<MQConfigurationProperties> list) {
this.list = list;
}
}
As in the previous example, for each one of the servers we need to create an specific ConnectionFactory and JmsListenerContainerFactory. This is done using JmsListenerConfigurer that allows the creation of listeners programatically.
@Configuration
@EnableJms
public class JmsConfig implements JmsListenerConfigurer {
@Autowired
private ObjectProvider<List<MQConnectionFactoryCustomizer>> factoryCustomizers;
@Autowired
private DefaultJmsListenerContainerFactoryConfigurer configurer;
@Autowired
private QmProperties qmProperties;
@Autowired
private QueueConsumer queueConsumer;
@Value("${example.queue}")
private String destination;
@Override
public void configureJmsListeners(JmsListenerEndpointRegistrar registrar) {
for (MQConfigurationProperties properties : qmProperties.getList()) {
String queueManager = properties.getQueueManager();
MQConnectionFactory connectionFactory = new MQConnectionFactoryFactory(properties, factoryCustomizers.getIfAvailable()).createConnectionFactory(MQConnectionFactory.class);
DefaultJmsListenerContainerFactory factory = new DefaultJmsListenerContainerFactory();
configurer.configure(factory, connectionFactory);
SimpleJmsListenerEndpoint endpoint = new SimpleJmsListenerEndpoint();
endpoint.setId("jmsEndpoint-" + queueManager);
endpoint.setDestination(destination);
endpoint.setMessageListener(message -> {
try {
queueConsumer.receive(queueManager, message.getBody(String.class));
} catch (JMSException e) {
throw new RuntimeException(e);
}
});
registrar.registerEndpoint(endpoint, factory);
}
}
}
The QueueConsumer bean will be registered for each of the queue managers the present in the configuration.
Note that we removed the @JmsListener because the QueueConsumer bean will be registered by our JmsConfig.
@Component
public class QueueConsumer {
public void receive(String queueManeger, String text) {
System.out.println("Received from " + queueManeger + ": " + text);
}
}
Featured ones: