Click here to close now.


Industrial IoT Authors: Bob Gourley, Ken Simpson, Peter Silva, Dana Gardner, Elizabeth White

Related Topics: Industrial IoT

Industrial IoT: Article

When Should Java And XML Be Used For Messaging?

When Should Java And XML Be Used For Messaging?

When does it make sense to use JMS (Java Message Service) and XML to support a heterogeneous messaging environment? Most buzzword-compliant people talk about JMS and XML when thinking about developing a messaging solution for their organization.

While in most cases this is the correct answer, we need to understand the requirements we're trying to fulfill before giving an answer. For example:

  • Can the solution be deployed using asynchronous communications or does it require synchronous behavior?
  • Will the solution be used in the intranet or extranet?
  • What are the messaging paradigms supported by your system?
  • Does the underlying messaging system support JMS?
  • What qualities of service (QoS) are supported by the messaging system?
  • What are the characteristics of the information to be published on the network?
  • Are e-mail messages a requirement?
  • What are the possible messaging systems the solution will be deploying against?
In short, we need to understand the characteristics of the problem before we can justify the use of any technology - in this case JMS and XML. Let me first give a brief introduction to JMS and explain the role of XML. My goal this month is to help you understand the requirements that XML and JMS are attempting to meet.

Sun, IBM, Modulus, NEON, OpenHorizon, Oracle, TIBCO, and Vitria developed the JMS specification. The purpose was to define a common API that would enable Java developers to use the same messaging system. In the JMS specification there's a clear distinction between the application and the message provider layers. The software developer is responsible for coding his or her application against the JMS interfaces; the message provider is responsible for coding the implementation to the interfaces. The idea behind this approach is to decouple the client application from the specifics of the messaging system. This allows the message provider layer to plug into the application layer. JMS defines two types of messaging paradigms:

  • Point-to-point
  • Publish/subscribe
The point-to-point paradigm follows a producer/consumer pattern that allows the producer application to write information to a queue and a consumer application to read it from the queue (see Figure 1). The queue mechanism identifies the decoupling point between the producer application and the consumer application. The producer application doesn't depend on the consumer application to access the queue to write to it, or vice versa. Some messaging systems provide QoS that enables persistence of the information stored inside a queue.

The publish/subscribe paradigm follows an observer pattern with explicit interest defined (see Figure 2). This approach allows subscriber applications to specify the types of events they're interested in receiving and allows the publishing application to broadcast messages independent of interested parties. The mapping between interested subscribers and published content is facilitated by the messaging system. This allows subscribers to publish information totally independent of recipients and vice versa. Some messaging systems provide QoS that enables the persistence of published messages for future processing.

JMS developers are responsible for selecting the message provider and for specifying the type of messaging model they want to implement. In addition, some JMS services are supported by the JMS layer independent of the underlying messaging implementation. These are:

  • Transactions
  • Message filtering
These need to be supported by the JMS provider implementation layer, however.

Most messaging systems, including the JMS specification, are agnostic when it comes to message content. They categorize message content as:

  • Basic types (int, float, char, long, etc.)
  • Text (string)
  • Bytes (byte arrays)
This is where XML comes to the rescue by providing the mechanisms to define the content of a message. This information is used by both sender and receiver clients to manipulate complex objects. The XML tags allow the sender application to serialize an object for future consumption by the receiver application. It's the responsibility of the receiver application to reconstruct the object for further manipulation.

Another advantage of using XML for defining the content of a message is that it provides a platform-independent mechanism for exchanging information between heterogeneous applications. This means a Visual Basic application can package an object using XML and send it to a Java application where it can be reconstructed from the XML message.

It's important to realize that XML doesn't provide a communications transport like TIBCO, MQSeries, IIOP, SMTP, and HTTP. However, it can work with any of these transports to provide message- content abstraction. One example of how XML facilitates the creation of communication transport is the use of HTTP and XML to develop XML RPCs.

Does this mean that the buzzword-compliant people know best? I don't think so! However, they pay enough attention to know what the technologists are saying. As mentioned earlier, JMS provides a communication abstraction layer for messaging while XML provides a message content abstraction layer. JMS enables the use of XML via its TextMessage content type. This enables string-based messages and XML text (see Listing 1).

When JMS and XML?
JMS and XML provide a total abstraction of communications transport and data content. Given this statement, why should you care about any requirements? Isn't this the solution to all your messaging needs? Let's revisit the questions asked earlier:

Q: Can the solution be deployed using asynchronous communications or does it require synchronous behavior?
A: JMS deals with asynchronous communications. If you need to manipulate synchronous flows like RMI, CORBA, or HTTP, you may want to consider using synchronous protocols. While you can implement synchronous behavior with asynchronous protocols, this isn't the norm and it's more difficult.

Q: Will this solution be used in the intranet or extranet?
A: JMS deals with messaging in thje intranet. Publish/subscribe and queue management systems aren't designed to deal with unreliable networks like the Internet. If you want to set up extranet communications, you need to consider XML RPC (SOAP) or SMTP (e-mail).

Q: What are the messaging paradigms supported by your system?
A: Does the underlying system support publish/subscribe or point-to-point? Some systems support only one or the other. Publish/subscribe systems have been optimized for broadcast (e,g., TIBCO). They haven't been optimized for point-to-point. Similarly, queue management systems have been optimized to provide message persistence via queues and point-to-point communications. They haven't been optimized for publish/subscribe.

Q: Does the underlying messaging system support JMS?
A: If your corporate messaging system doesn't support JMS, you may be stuck with their proprietary Java interfaces or you may need to develop your own JNI interfaces.

Q: What QoS are supported by the messaging system?
A: Does the JMS implementation that comes with your messaging system support guaranteed delivery, transactions, and message filtering? If your application requires transactions and your JMS implementation doesn't support them, this may be a problem. You may be forced to evaluate a different JMS provider. If your JMS provider supports message persistence, where is the persistence storage happening, in an RDBMS or proprietary storage? Persistence may be an issue if your JMS provider requires you to purchase a specific RDBMS.

Q: What are the characteristics of the information to be published on the network?
A: If you're using publish/subscribe, what type of information are you publishing? This issue is particularly important if you're using publishing as an event mechanism. Events are normally regarded as lightweight messages. Because of this requirement, it may not make sense to inquire about the overhead of wrapping a simple event value in an XML message. The subscribers may be listening on a topic called shipping orders, and the only content inside the event may be the order number. In this situation there's no need to create an XML message to publish the information. However, if subscribers are listening for the complete order with all of its parameters, it makes sense to package the order object inside an XML message for further processing by the subscriber application.

Q: Are e-mail messages a requirement?
A: JMS doesn't handle e-mail sending or receiving. That's the purpose of the JavaMail APIs. If the application needs to support e-mail for asynchronous messaging, then JMS isn't the answer. However, if your application needs to use an intranet-based messaging system like TIBCO, and you want to implement an e-mail gateway, the combination of JMS and JavaMail is ideal.

Q: What are the possible messaging systems that the solution will be deployed against?
A: If the solution being developed will be used only against one messaging system, it may not make sense to use JMS. This is the case if there's no JMS provider for a particular messaging framework but there is a Java API for that system. However, if the solution can be deployed against multiple messaging systems, it makes sense to leverage a communications abstraction layer.

JMS and XML are an ideal combination and can be deployed to provide a total abstraction solution for messaging and data content. However, you need to understand your requirements clearly before making the technology call. Therefore, it's important to know the limitations and correct usage of the JMS and XML technologies.

More Stories By Israel Hilerio

Israel Hilerio is a program manager at Microsoft in the Windows Workflow Foundation team. He has 15+ years of development experience doing business applications and has a PhD in Computer Science.

Comments (0)

Share your thoughts on this story.

Add your comment
You must be signed in to add a comment. Sign-in | Register

In accordance with our Comment Policy, we encourage comments that are on topic, relevant and to-the-point. We will remove comments that include profanity, personal attacks, racial slurs, threats of violence, or other inappropriate material that violates our Terms and Conditions, and will block users who make repeated violations. We ask all readers to expect diversity of opinion and to treat one another with dignity and respect.

@ThingsExpo Stories
Container technology is shaping the future of DevOps and it’s also changing the way organizations think about application development. With the rise of mobile applications in the enterprise, businesses are abandoning year-long development cycles and embracing technologies that enable rapid development and continuous deployment of apps. In his session at DevOps Summit, Kurt Collins, Developer Evangelist at, examined how Docker has evolved into a highly effective tool for application delivery by allowing increasingly popular Mobile Backend-as-a-Service (mBaaS) platforms to quickly crea...
Discussions of cloud computing have evolved in recent years from a focus on specific types of cloud, to a world of hybrid cloud, and to a world dominated by the APIs that make today's multi-cloud environments and hybrid clouds possible. In this Power Panel at 17th Cloud Expo, moderated by Conference Chair Roger Strukhoff, panelists addressed the importance of customers being able to use the specific technologies they need, through environments and ecosystems that expose their APIs to make true change and transformation possible.
With major technology companies and startups seriously embracing IoT strategies, now is the perfect time to attend @ThingsExpo 2016 in New York and Silicon Valley. Learn what is going on, contribute to the discussions, and ensure that your enterprise is as "IoT-Ready" as it can be! Internet of @ThingsExpo, taking place Nov 3-5, 2015, at the Santa Clara Convention Center in Santa Clara, CA, is co-located with 17th Cloud Expo and will feature technical sessions from a rock star conference faculty and the leading industry players in the world. The Internet of Things (IoT) is the most profound cha...
Internet of @ThingsExpo, taking place June 7-9, 2016 at Javits Center, New York City and Nov 1-3, 2016, at the Santa Clara Convention Center in Santa Clara, CA, is co-located with the 18th International @CloudExpo and will feature technical sessions from a rock star conference faculty and the leading industry players in the world and ThingsExpo New York Call for Papers is now open.
The cloud. Like a comic book superhero, there seems to be no problem it can’t fix or cost it can’t slash. Yet making the transition is not always easy and production environments are still largely on premise. Taking some practical and sensible steps to reduce risk can also help provide a basis for a successful cloud transition. A plethora of surveys from the likes of IDG and Gartner show that more than 70 percent of enterprises have deployed at least one or more cloud application or workload. Yet a closer inspection at the data reveals less than half of these cloud projects involve production...
Growth hacking is common for startups to make unheard-of progress in building their business. Career Hacks can help Geek Girls and those who support them (yes, that's you too, Dad!) to excel in this typically male-dominated world. Get ready to learn the facts: Is there a bias against women in the tech / developer communities? Why are women 50% of the workforce, but hold only 24% of the STEM or IT positions? Some beginnings of what to do about it! In her Day 2 Keynote at 17th Cloud Expo, Sandy Carter, IBM General Manager Cloud Ecosystem and Developers, and a Social Business Evangelist, wil...
Cloud computing delivers on-demand resources that provide businesses with flexibility and cost-savings. The challenge in moving workloads to the cloud has been the cost and complexity of ensuring the initial and ongoing security and regulatory (PCI, HIPAA, FFIEC) compliance across private and public clouds. Manual security compliance is slow, prone to human error, and represents over 50% of the cost of managing cloud applications. Determining how to automate cloud security compliance is critical to maintaining positive ROI. Raxak Protect is an automated security compliance SaaS platform and ma...
In his keynote at @ThingsExpo, Chris Matthieu, Director of IoT Engineering at Citrix and co-founder and CTO of Octoblu, focused on building an IoT platform and company. He provided a behind-the-scenes look at Octoblu’s platform, business, and pivots along the way (including the Citrix acquisition of Octoblu).
There are over 120 breakout sessions in all, with Keynotes, General Sessions, and Power Panels adding to three days of incredibly rich presentations and content. Join @ThingsExpo conference chair Roger Strukhoff (@IoT2040), June 7-9, 2016 in New York City, for three days of intense 'Internet of Things' discussion and focus, including Big Data's indespensable role in IoT, Smart Grids and Industrial Internet of Things, Wearables and Consumer IoT, as well as (new) IoT's use in Vertical Markets.
Today air travel is a minefield of delays, hassles and customer disappointment. Airlines struggle to revitalize the experience. GE and M2Mi will demonstrate practical examples of how IoT solutions are helping airlines bring back personalization, reduce trip time and improve reliability. In their session at @ThingsExpo, Shyam Varan Nath, Principal Architect with GE, and Dr. Sarah Cooper, M2Mi’s VP Business Development and Engineering, explored the IoT cloud-based platform technologies driving this change including privacy controls, data transparency and integration of real time context with p...
The Internet of Things (IoT) is growing rapidly by extending current technologies, products and networks. By 2020, Cisco estimates there will be 50 billion connected devices. Gartner has forecast revenues of over $300 billion, just to IoT suppliers. Now is the time to figure out how you’ll make money – not just create innovative products. With hundreds of new products and companies jumping into the IoT fray every month, there’s no shortage of innovation. Despite this, McKinsey/VisionMobile data shows "less than 10 percent of IoT developers are making enough to support a reasonably sized team....
We all know that data growth is exploding and storage budgets are shrinking. Instead of showing you charts on about how much data there is, in his General Session at 17th Cloud Expo, Scott Cleland, Senior Director of Product Marketing at HGST, showed how to capture all of your data in one place. After you have your data under control, you can then analyze it in one place, saving time and resources.
Just over a week ago I received a long and loud sustained applause for a presentation I delivered at this year’s Cloud Expo in Santa Clara. I was extremely pleased with the turnout and had some very good conversations with many of the attendees. Over the next few days I had many more meaningful conversations and was not only happy with the results but also learned a few new things. Here is everything I learned in those three days distilled into three short points.
As organizations realize the scope of the Internet of Things, gaining key insights from Big Data, through the use of advanced analytics, becomes crucial. However, IoT also creates the need for petabyte scale storage of data from millions of devices. A new type of Storage is required which seamlessly integrates robust data analytics with massive scale. These storage systems will act as “smart systems” provide in-place analytics that speed discovery and enable businesses to quickly derive meaningful and actionable insights. In his session at @ThingsExpo, Paul Turner, Chief Marketing Officer at...
DevOps is about increasing efficiency, but nothing is more inefficient than building the same application twice. However, this is a routine occurrence with enterprise applications that need both a rich desktop web interface and strong mobile support. With recent technological advances from Isomorphic Software and others, rich desktop and tuned mobile experiences can now be created with a single codebase – without compromising functionality, performance or usability. In his session at DevOps Summit, Charles Kendrick, CTO and Chief Architect at Isomorphic Software, demonstrated examples of com...
In his General Session at 17th Cloud Expo, Bruce Swann, Senior Product Marketing Manager for Adobe Campaign, explored the key ingredients of cross-channel marketing in a digital world. Learn how the Adobe Marketing Cloud can help marketers embrace opportunities for personalized, relevant and real-time customer engagement across offline (direct mail, point of sale, call center) and digital (email, website, SMS, mobile apps, social networks, connected objects).
The Internet of Everything is re-shaping technology trends–moving away from “request/response” architecture to an “always-on” Streaming Web where data is in constant motion and secure, reliable communication is an absolute necessity. As more and more THINGS go online, the challenges that developers will need to address will only increase exponentially. In his session at @ThingsExpo, Todd Greene, Founder & CEO of PubNub, exploreed the current state of IoT connectivity and review key trends and technology requirements that will drive the Internet of Things from hype to reality.
Two weeks ago (November 3-5), I attended the Cloud Expo Silicon Valley as a speaker, where I presented on the security and privacy due diligence requirements for cloud solutions. Cloud security is a topical issue for every CIO, CISO, and technology buyer. Decision-makers are always looking for insights on how to mitigate the security risks of implementing and using cloud solutions. Based on the presentation topics covered at the conference, as well as the general discussions heard between sessions, I wanted to share some of my observations on emerging trends. As cyber security serves as a fou...
Continuous processes around the development and deployment of applications are both impacted by -- and a benefit to -- the Internet of Things trend. To help better understand the relationship between DevOps and a plethora of new end-devices and data please welcome Gary Gruver, consultant, author and a former IT executive who has led many large-scale IT transformation projects, and John Jeremiah, Technology Evangelist at Hewlett Packard Enterprise (HPE), on Twitter at @j_jeremiah. The discussion is moderated by me, Dana Gardner, Principal Analyst at Interarbor Solutions.
Too often with compelling new technologies market participants become overly enamored with that attractiveness of the technology and neglect underlying business drivers. This tendency, what some call the “newest shiny object syndrome” is understandable given that virtually all of us are heavily engaged in technology. But it is also mistaken. Without concrete business cases driving its deployment, IoT, like many other technologies before it, will fade into obscurity.