Book Image

Domain-Driven Design with Java - A Practitioner’s Guide

By : Premanand Chandrasekaran, Karthik Krishnan
Book Image

Domain-Driven Design with Java - A Practitioner’s Guide

By: Premanand Chandrasekaran, Karthik Krishnan

Overview of this book

Domain-Driven Design (DDD) makes available a set of techniques and patterns that enable domain experts, architects, and developers to work together to decompose complex business problems into a set of well-factored, collaborating, and loosely coupled subsystems. This practical guide will help you as a developer and architect to put your knowledge to work in order to create elegant software designs that are enjoyable to work with and easy to reason about. You'll begin with an introduction to the concepts of domain-driven design and discover various ways to apply them in real-world scenarios. You'll also appreciate how DDD is extremely relevant when creating cloud native solutions that employ modern techniques such as event-driven microservices and fine-grained architectures. As you advance through the chapters, you'll get acquainted with core DDD’s strategic design concepts such as the ubiquitous language, context maps, bounded contexts, and tactical design elements like aggregates and domain models and events. You'll understand how to apply modern, lightweight modeling techniques such as business value canvas, Wardley mapping, domain storytelling, and event storming, while also learning how to test-drive the system to create solutions that exhibit high degrees of internal quality. By the end of this software design book, you'll be able to architect, design, and implement robust, resilient, and performant distributed software solutions.
Table of Contents (17 chapters)
1
Part 1: Foundations
4
Part 2: Real-World DDD
12
Part 3: Evolution Patterns

Versioning

When we are working with a monolithic application, we have large portions bundled as a single cohesive unit. This means that other than third-party dependencies, we don’t have to worry about explicitly versioning our own components. However, when we start breaking components into their individual deployable units, there is a need to pay careful attention to how the components, APIs, and data elements of our solution are versioned. Let’s look at each in turn.

Components

When we create components, there are two broad categories – those that are deployed on their own and those that are embedded within another component. In the case of deployable components, there is a need to use an explicit version to identify specific instances of the component, even if only for deployment purposes. In the case of the embedded component, again there is a need to use an explicit version because other components need to understand what instance they depend upon. In...