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

Enhancing shared understanding

When working with a problem where domain concepts are unclear, there is a need to arrive at a common understanding among key team members (both those that have bright ideas – the business/product people, and those that translate those ideas into working software – the software developers). For this process to be effective, we tend to look for approaches that are as follows:

  • Quick, informal, and effective
  • Collaborative – easy to learn and adopt for both non-technical and technical team members
  • Pictorial, because a picture can be worth a thousand words
  • Usable for both coarse-grained and fine-grained scenarios

There are several means to arrive at this shared understanding. The following are some of the commonly used approaches:

  • UML
  • BPMN
  • Use cases
  • User story mapping
  • CRC models
  • Data flow diagrams

These modeling techniques try to formalize knowledge and express it in the form...