Welcome!

XML Authors: Carmen Gonzalez, Kevin Benedict, Elizabeth White, Rich Waidmann, Jason Bloomberg

Related Topics: SOA & WOA, Java, XML, .NET, Web 2.0, Security

SOA & WOA: Book Review

Book Review: Implementing Domain-Driven Design

Will take your skills to the next level

Agile is not easy and implementing Domain-Driven Design (DDD) is not easy. I think my favorite part of the book is that the author realizes that, and also has a realistic perspective on what it takes to successfully use agile processes and DDD.

The book starts out with a really nice overview of DDD. By the time you are done the first chapter you have a pretty good high level picture of what DDD is all about. One topic he really drives home is Ubiquitous Language.

Ubiquitous Language is a shared team language that defines a certain domain. When you are reading about Ubiquitous Language it may seem like something that just happens on its own. It isn't. An explicit domain language should be defined, it should not just be allowed to implicitly come about. This same concept has been around for years in Water Fall, Unified Process, RUP, and other processes. It has always been a very important part of the software development process, so don't discount it.

Chapter 1 also does a great job of providing tips on how to show the business value of using DDD. The author has a clear understanding that without the support of the business you aren't going to get very far with your project, and in order to get them onboard you need to show them what they will gain by supporting DDD.

The remaining chapters dig into the details of DDD. I have listed the chapters below. Their titles are pretty self-explanatory.

Chapter 1. Getting Started with DDD
Chapter 2. Domains, Subdomains, and Bounded Contexts
Chapter 3. Context Maps
Chapter 4. Architecture
Chapter 5. Entities
Chapter 6. Value Objects
Chapter 7. Services
Chapter 8. Domain Events
Chapter 9. Modules
Chapter 10. Aggregates
Chapter 11. Factories
Chapter 12. Repositories
Chapter 13. Integrating Bounded Contexts
Chapter 14. Application
Appendix A. Aggregates and Event Sourcing: A+ES

I have seen a lot of teams that could not build software with UP or RUP adopt Scrum in hopes that changing the process will make a difference. It never does. There are a variety of reasons including not doing any architecture, not having experienced developers with the right skill sets, not having the right business users involved, not having the requirements elicitation skills needed, and the list can go on and on. The author clearly understands Scrum is not a silver bullet. I mention this because DDD done correctly can give agile processes a much better chance at success, but you must have the skills on the team in order pull it off.

I was really glad to see the author included a chapter on architecture. The author does a great job of covering a ton of architectural styles and patterns. Patterns, styles, and topic found in the Architecture chapter include Layers Architecture with the Dependency Inversion Principle, Hexagonal Architecture, SOA environment, REST, Data Fabric, Grid-Based Distributed Cache, and CQRS.

Every chapter is an in depth look at the topic of the given chapter. I did not leave any of the chapters feeling like I missed something. I have read both Domain-Driven Design: Tackling Complexity in the Heart of Software and Patterns of Enterprise Application Architecture, and I had both handy for looking up references to them. It is not necessary to read them first, but it did help that I had.

I am not going to say using DDD is easy, but I will say this book can definitely get you to where you can successfully use it. The author's writing style is really good and he is good at making the book entertaining. I will however say this, be prepared to read the entire book if you want to get to that point of successfully using DDD. There is a lot to learn, but it is worth it.

I highly recommend this book to every software architect and developer. Even if you don't go all out DDD there is a ton of great advice and wisdom found in this book that will help you improve your skills.

Implementing Domain-Driven Design

More Stories By Tad Anderson

Tad Anderson has been doing Software Architecture for 18 years and Enterprise Architecture for the past few.

@ThingsExpo Stories
The Internet of Things will greatly expand the opportunities for data collection and new business models driven off of that data. In her session at @ThingsExpo, Esmeralda Swartz, CMO of MetraTech, discussed how for this to be effective you not only need to have infrastructure and operational models capable of utilizing this new phenomenon, but increasingly service providers will need to convince a skeptical public to participate. Get ready to show them the money!
The Industrial Internet revolution is now underway, enabled by connected machines and billions of devices that communicate and collaborate. The massive amounts of Big Data requiring real-time analysis is flooding legacy IT systems and giving way to cloud environments that can handle the unpredictable workloads. Yet many barriers remain until we can fully realize the opportunities and benefits from the convergence of machines and devices with Big Data and the cloud, including interoperability, data security and privacy.
The 3rd International Internet of @ThingsExpo, co-located with the 16th International Cloud Expo - to be held June 9-11, 2015, at the Javits Center in New York City, NY - announces that its Call for Papers is now open. The Internet of Things (IoT) is the biggest idea since the creation of the Worldwide Web more than 20 years ago.
Cloud Expo 2014 TV commercials will feature @ThingsExpo, which was launched in June, 2014 at New York City's Javits Center as the largest 'Internet of Things' event in the world.
"People are a lot more knowledgeable about APIs now. There are two types of people who work with APIs - IT people who want to use APIs for something internal and the product managers who want to do something outside APIs for people to connect to them," explained Roberto Medrano, Executive Vice President at SOA Software, in this SYS-CON.tv interview at Cloud Expo, held Nov 4–6, 2014, at the Santa Clara Convention Center in Santa Clara, CA.
SYS-CON Media announced that Splunk, a provider of the leading software platform for real-time Operational Intelligence, has launched an ad campaign on Big Data Journal. Splunk software and cloud services enable organizations to search, monitor, analyze and visualize machine-generated big data coming from websites, applications, servers, networks, sensors and mobile devices. The ads focus on delivering ROI - how improved uptime delivered $6M in annual ROI, improving customer operations by mining large volumes of unstructured data, and how data tracking delivers uptime when it matters most.
DevOps Summit 2015 New York, co-located with the 16th International Cloud Expo - to be held June 9-11, 2015, at the Javits Center in New York City, NY - announces that it is now accepting Keynote Proposals. The widespread success of cloud computing is driving the DevOps revolution in enterprise IT. Now as never before, development teams must communicate and collaborate in a dynamic, 24/7/365 environment. There is no time to wait for long development cycles that produce software that is obsolete at launch. DevOps may be disruptive, but it is essential.
Wearable devices have come of age. The primary applications of wearables so far have been "the Quantified Self" or the tracking of one's fitness and health status. We propose the evolution of wearables into social and emotional communication devices. Our BE(tm) sensor uses light to visualize the skin conductance response. Our sensors are very inexpensive and can be massively distributed to audiences or groups of any size, in order to gauge reactions to performances, video, or any kind of presentation. In her session at @ThingsExpo, Jocelyn Scheirer, CEO & Founder of Bionolux, will discuss ho...
We’re no longer looking to the future for the IoT wave. It’s no longer a distant dream but a reality that has arrived. It’s now time to make sure the industry is in alignment to meet the IoT growing pains – cooperate and collaborate as well as innovate. In his session at @ThingsExpo, Jim Hunter, Chief Scientist & Technology Evangelist at Greenwave Systems, will examine the key ingredients to IoT success and identify solutions to challenges the industry is facing. The deep industry expertise behind this presentation will provide attendees with a leading edge view of rapidly emerging IoT oppor...
“With easy-to-use SDKs for Atmel’s platforms, IoT developers can now reap the benefits of realtime communication, and bypass the security pitfalls and configuration complexities that put IoT deployments at risk,” said Todd Greene, founder & CEO of PubNub. PubNub will team with Atmel at CES 2015 to launch full SDK support for Atmel’s MCU, MPU, and Wireless SoC platforms. Atmel developers now have access to PubNub’s secure Publish/Subscribe messaging with guaranteed ¼ second latencies across PubNub’s 14 global points-of-presence. PubNub delivers secure communication through firewalls, proxy ser...
The 3rd International Internet of @ThingsExpo, co-located with the 16th International Cloud Expo - to be held June 9-11, 2015, at the Javits Center in New York City, NY - announces that its Call for Papers is now open. The Internet of Things (IoT) is the biggest idea since the creation of the Worldwide Web more than 20 years ago.
Connected devices and the Internet of Things are getting significant momentum in 2014. In his session at Internet of @ThingsExpo, Jim Hunter, Chief Scientist & Technology Evangelist at Greenwave Systems, examined three key elements that together will drive mass adoption of the IoT before the end of 2015. The first element is the recent advent of robust open source protocols (like AllJoyn and WebRTC) that facilitate M2M communication. The second is broad availability of flexible, cost-effective storage designed to handle the massive surge in back-end data in a world where timely analytics is e...
"There is a natural synchronization between the business models, the IoT is there to support ,” explained Brendan O'Brien, Co-founder and Chief Architect of Aria Systems, in this SYS-CON.tv interview at the 15th International Cloud Expo®, held Nov 4–6, 2014, at the Santa Clara Convention Center in Santa Clara, CA.
The Internet of Things will put IT to its ultimate test by creating infinite new opportunities to digitize products and services, generate and analyze new data to improve customer satisfaction, and discover new ways to gain a competitive advantage across nearly every industry. In order to help corporate business units to capitalize on the rapidly evolving IoT opportunities, IT must stand up to a new set of challenges. In his session at @ThingsExpo, Jeff Kaplan, Managing Director of THINKstrategies, will examine why IT must finally fulfill its role in support of its SBUs or face a new round of...
The BPM world is going through some evolution or changes where traditional business process management solutions really have nowhere to go in terms of development of the road map. In this demo at 15th Cloud Expo, Kyle Hansen, Director of Professional Services at AgilePoint, shows AgilePoint’s unique approach to dealing with this market circumstance by developing a rapid application composition or development framework.

ARMONK, N.Y., Nov. 20, 2014 /PRNewswire/ --  IBM (NYSE: IBM) today announced that it is bringing a greater level of control, security and flexibility to cloud-based application development and delivery with a single-tenant version of Bluemix, IBM's platform-as-a-service. The new platform enables developers to build ap...

Building low-cost wearable devices can enhance the quality of our lives. In his session at Internet of @ThingsExpo, Sai Yamanoor, Embedded Software Engineer at Altschool, provided an example of putting together a small keychain within a $50 budget that educates the user about the air quality in their surroundings. He also provided examples such as building a wearable device that provides transit or recreational information. He then reviewed the resources available to build wearable devices at home including open source hardware, the raw materials required and the options available to power s...
An entirely new security model is needed for the Internet of Things, or is it? Can we save some old and tested controls for this new and different environment? In his session at @ThingsExpo, New York's at the Javits Center, Davi Ottenheimer, EMC Senior Director of Trust, reviewed hands-on lessons with IoT devices and reveal a new risk balance you might not expect. Davi Ottenheimer, EMC Senior Director of Trust, has more than nineteen years' experience managing global security operations and assessments, including a decade of leading incident response and digital forensics. He is co-author of t...
The Internet of Things promises to transform businesses (and lives), but navigating the business and technical path to success can be difficult to understand. In his session at @ThingsExpo, Sean Lorenz, Technical Product Manager for Xively at LogMeIn, demonstrated how to approach creating broadly successful connected customer solutions using real world business transformation studies including New England BioLabs and more.
The Internet of Things is not new. Historically, smart businesses have used its basic concept of leveraging data to drive better decision making and have capitalized on those insights to realize additional revenue opportunities. So, what has changed to make the Internet of Things one of the hottest topics in tech? In his session at @ThingsExpo, Chris Gray, Director, Embedded and Internet of Things, discussed the underlying factors that are driving the economics of intelligent systems. Discover how hardware commoditization, the ubiquitous nature of connectivity, and the emergence of Big Data a...