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)
Part 1: Foundations
Part 2: Real-World DDD
Part 3: Evolution Patterns

Bounded context relationships

We need bounded contexts to be as independent as possible. However, this does not mean that bounded contexts are completely isolated from each other. Bounded contexts need to collaborate with others to provide business value. Whenever there is collaboration required between two bounded contexts, the nature of their relationship is not only influenced by their individual goals and priorities but also by the prevailing organizational realities. In a high-performing environment, it is fairly common to have a single team assume ownership of a bounded context. The relationships between the teams owning these bounded contexts play a significant role in influencing the integration patterns employed to arrive at a solution. At a high level, there are two categories of relationships:

  • Symmetric
  • Asymmetric

Let’s look at these relationship types in more detail.

Symmetric relationship patterns

Two teams, say team A and team B, can be...