New in JMS 2.0 . . .

This post lists ALL of the new APIs (interfaces/classes/annotations etc.) introduced in JMS 2.0 (part of the Java EE 7 platform). These have been categorized as follows

• API simplification
• Ease of use
• Exception Handling
• Miscellaneous

Here is a quick summary along with some code snippets

API simplification

JMSContext

Simpler abstraction on top of Connection and Session objects which eliminates the need for interacting with these classes/interfaces in order to send/receive messages.

	@Path("email")
	@Stateless
	public class EmailService {
	//pulls in default Conn Factory as per Java EE 7
	@Resource
	ConnectionFactory cf;
	//application managed
	JMSContext ctx;
	@Resource("jms/emailQ")
	Destination emailQ;
	@POST
	public void send(String email) {
	Session session;
	try {
	ctx = cf.createContext();
	ctx.createProducer().send(emailQ, email);
	System.out.println("Message Sent to queue – " + ((Queue) emailQ).getQueueName());
	} catch (JMSException ex) {
	Logger.getLogger(EmailService.class.getName()).log(Level.SEVERE, null, ex);
	throw new JMSRuntimeException(ex.getMessage(), ex.getMessage(), ex);
	} finally {
	//clean up after use. Can also be done as inside a @PreDestroy callback method
	ctx.close();
	System.out.println("JMSContext closed");
	}
	}
	}

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EmailService.java

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JMSConnectionFactory

Used during JMSContext injection to specify the JNDI name of the JMS ConnectionFactory

	@Path("email")
	@Stateless
	public class TheBestEmailService {
	//container managed
	@Inject
	@JMSConnectionFactory("jms/myConnectionFactory")
	JMSContext ctx;
	@Resource("jms/emailQ")
	Destination emailQ;
	@POST
	public void send(String email) {
	Session session;
	try {
	ctx.createProducer().send(emailQ, email);
	System.out.println("Message Sent to queue – " + ((Queue) emailQ).getQueueName());
	} catch (JMSException ex) {
	Logger.getLogger(TheBestEmailService.class.getName()).log(Level.SEVERE, null, ex);
	throw new JMSRuntimeException(ex.getMessage(), ex.getMessage(), ex);
	}
	}
	}

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TheBestEmailService.java

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JMSProducer and JMSConsumer

As the name suggests, a JMSProducer and JMSConsumer encapsulate the process of sending JMS messages to and from destinations (topics and queues), respectively. Instances to these objects can be obtained from the JMSContext object and they are important from an API ease-of-use perspective. Here is a ‘fluent’ API example

	context.createProducer().send(queue,message);
	context.createConsumer(topic).receiveBody(Mail.class);

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jms_consumer_producer.txt

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XAJMSContext

Transactional equivalent of the vanilla JMSContext object. The implementation of this interface provides support for JTA within JMS

Ease of use

These annotations empower less reliance on manual/administrative configuration and drive automated deployment of Java EE applications. These are perfect examples of ‘configuration as code’ and invaluable in Cloud (PaaS) deployment scenarios

JMSConnectionFactoryDefinition and JMSConnectionFactoryDefinitions

Specify the JNDI name of one/multiple JMS ConnectionFactory object. This resource will be automatically provisioned at deployment time

	@JMSConnectionFactoryDefinition(name = "jndi/App1JMSConnFactory")
	@JMSConnectionFactoryDefinitions({@JMSConnectionFactoryDefinition(name = "jndi/App2JMSConnFactory"),
	@JMSConnectionFactoryDefinition(name = "jndi/App3JMSConnFactory")})

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JMSConnectionFactoryDefinition.txt

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JMSDestinationDefinition and JMSDestinationDefinitions

Specify the JNDI name of one/more JMS Destinations (queues/topics). This resource will be automatically provisioned at deployment time

	@JMSDestinationDefinition(name = "jms/emailQueue", interfaceName = "javax.jms.Queue")
	@JMSDestinationDefinitions({@JMSDestinationDefinition(name = "portal/notificationQueue", interfaceName = "javax.jms.Queue"),
	@JMSDestinationDefinition(name = "app/stockPriceTopic", interfaceName = "javax.jms.Topic")})

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JMSDestinationDefinition.txt

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Exception Handling

JMS 1.1 and earlier versions did not have a notion of unchecked exceptions. From JMS 2.0, JMSRuntimeException has been introduced to act as the base/parent from which all other unchecked exceptions have been extended. Here is a list all the new exceptions introduced in JMS 2.0 (these are mostly unchecked versions of their checked counterparts)

• JMSRuntimeException
• IllegalStateRuntimeException
• InvalidClientIDRuntimeException
• InvalidDestinationRuntimeException
• InvalidSelectorRuntimeException
• JMSSecurityRuntimeException
• MessageFormatRuntimeException
• MessageNotWriteableRuntimeException
• ResourceAllocationRuntimeException
• TransactionInProgressRuntimeException
• TransactionRolledBackRuntimeException

Miscellaneous

JMSPasswordCrdential

Used to secure access to JMS provider before attempting any operations using an injected JMSContext object

	Option 1
	———
	@Inject
	@JMSConnectionFactory("jms/myConnectionFactory")
	@JMSPasswordCredential(password = "secret", userName = "admin")
	JMSContext ctx;
	—————————————————————-
	Option 2
	———
	//inject javax.jms.ConnectionFactory
	@Resource("jndi/AppJMSConnFactory")
	ConnectionFactory cf;
	//use it to create the JMSContext
	JMSContext ctx = cf.createContext("admin","secret");

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ProtectedJMSContext.txt

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JMSSessionMode

Specifies session mode to be used during JMSContext injection

	@Inject
	@JMSConnectionFactory("jms/myConnectionFactory")
	//Accepts an integer. Other options are: JMSContext.SESSION_TRANSACTED, JMSContext.CLIENT_ACKNOWLEDGE and JMSContext.DUPS_OK_ACKNOWLEDGE
	@JMSSessionMode(JMSContext.AUTO_ACKNOWLEDGE)
	JMSContext ctx;

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JMSSessionMode.txt

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That’s it for the new stuff in JMS 2.0 from an API perspective.

Cheers !

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