Book Image

Get Your Hands Dirty on Clean Architecture

By : Tom Hombergs
Book Image

Get Your Hands Dirty on Clean Architecture

By: Tom Hombergs

Overview of this book

Building for maintainability is key to keeping development costs low and processes easy. The second edition of Get Your Hands Dirty on Clean Architecture is here to equip you with the essential skills and knowledge to build maintainable software. With this comprehensive guide, you’ll explore the drawbacks of conventional layered architecture and the advantages of domain-centric styles such as Robert C. Martin's Clean Architecture and Alistair Cockburn's Hexagonal Architecture. Then, you’ll dive into hands-on explanations on how to convert hexagonal architecture into actual code. You'll learn in detail about different mapping strategies between the layers of hexagonal architecture and discover how to assemble the architectural elements into an application. Additionally, you’ll understand how to enforce architecture boundaries, which shortcuts produce what types of technical debt, and how, sometimes, it is a good idea to willingly take on those debts. By the end of this second edition, you'll be armed with a deep understanding of the hexagonal architecture style and be ready to create maintainable web applications that save money and time.
Table of Contents (13 chapters)

Assembling via Spring's Classpath Scanning

If we use the Spring Framework to assemble our application, the result is called the application context. The application context contains all objects that together make up the application ("beans" in Java lingo).

Spring offers several approaches to assemble an application context, each having its own advantages and drawbacks. Let's start by discussing the most popular (and most convenient) approach: classpath scanning.

With classpath scanning, Spring goes through all the classes that are available in the classpath and searches for classes that are annotated with the @Component annotation. The framework then creates an object from each of these classes. The classes should have a constructor that takes all required fields as an argument, like our AccountPersistenceAdapter from Chapter 6, Implementing a Persistence Adapter:

@RequiredArgsConstructor

@Component

class AccountPersistenceAdapter implements

    LoadAccountPort...