Designing Hexagonal Architecture with Java

Learn how to build robust, change-tolerable, and highly maintainable cloud-native Java applications with Hexagonal Architecture and Quarkus.Key FeaturesUse hexagonal architecture to increase maintainability and reduce technical debtLearn how to build systems that are simple to change and understandLeverage Quarkus to create modern cloud-native applicationsBook DescriptionWe live in a fast-evolving world with new technologies emerging every day, where enterprises are constantly changing in an unending quest to be more profitable. So how to develop software capable of handling such a high level of unpredictability? With this question in mind, this book explores how hexagonal architecture can help build robust, change-tolerable, maintainable, and cloud-native applications that can meet the needs of enterprises seeking to increase their profits while dealing with uncertainties. This book starts covering hexagonal architecture's building blocks, such as entities, use cases, ports, and adapters. You'll learn to assemble business code in the Domain hexagon, create features with ports and use cases in the Application hexagon, and make your software compatible with different technologies by employing adapters in the Framework hexagon. In this new edition, you will learn the differences between hexagonal and layered architecture and how to apply SOLID principles while developing a hexagonal system based on a real-world scenario. Finally, you'll get to grips with using Quarkus to turn your hexagonal application into a cloud-native system. By the end of this book, you'll be able to develop robust, flexible, and maintainable systems that will stand the test of time.What you will learnLearn how to apply SOLID principles with hexagonal architectureFind out how to assemble business rules algorithms using the specification design patternCombine domain-driven design techniques with hexagonal principles to create powerful domain modelsEmploy adapters to make the system support different protocols such as REST, gRPC, and WebSocketCreate a module and package structure based on hexagonal principlesUse Java modules to enforce dependency inversion and ensure isolation between software componentsImplement Quarkus DI to manage the life cycle of input and output portsWho this book is forThis book is for software architects and Java developers who want to improve code maintainability and enhance productivity with an architecture that allows changes in technology without compromising business logic, which is precisely what hexagonal architecture does. Intermediate knowledge of the Java programming language and familiarity with Jakarta EE will help you to get the most out of this book.

Davi Vieira is a software craftsman with a vested interest in the challenges faced by large enterprises in software design, development, and architecture. He has more than 10 years of experience constructing and maintaining complex, long-lasting, and mission-critical systems using object-oriented languages. He values the good lessons and the software development tradition left by others who came before him. Inspired by this software tradition, he develops and evolves his ideas.