Book Image

Architecting Modern Java EE Applications

By : Sebastian Daschner
Book Image

Architecting Modern Java EE Applications

By: Sebastian Daschner

Overview of this book

Java EE 8 brings with it a load of features, mainly targeting newer architectures such as microservices, modernized security APIs, and cloud deployments. This book will teach you to design and develop modern, business-oriented applications using Java EE 8. It shows how to structure systems and applications, and how design patterns and Domain Driven Design aspects are realized in the age of Java EE 8. You will learn about the concepts and principles behind Java EE applications, and how to effect communication, persistence, technical and cross-cutting concerns, and asynchronous behavior. This book covers Continuous Delivery, DevOps, infrastructure-as-code, containers, container orchestration technologies, such as Docker and Kubernetes, and why and especially how Java EE fits into this world. It also covers the requirements behind containerized, zero-dependency applications and how modern Java EE application servers support these approaches. You will also learn about automated, fast, and reliable software tests, in different test levels, scopes, and test technologies. This book covers the prerequisites and challenges of distributed systems that lead to microservice, shared-nothing architectures. The challenges and solutions of consistency versus scalability will further lead us to event sourcing, event-driven architectures, and the CQRS principle. This book also includes the nuts and bolts of application performance as well as how to realize resilience, logging, monitoring and tracing in a modern enterprise world. Last but not least the demands of securing enterprise systems are covered. By the end, you will understand the ins and outs of Java EE so that you can make critical design decisions that not only live up to, but also surpass your clients' expectations.
Table of Contents (22 chapters)
Title Page
Credits
Foreword
About the Author
Acknowledgments
About the Reviewer
www.PacktPub.com
Customer Feedback
Dedication
Preface
12
Appendix: Links and further resources

Requirements of well-crafted tests


Today's software world has agreed that tests are crucial to working software. But what makes a good software test? What software components do we have to test? And, more importantly, how can we develop well-crafted tests?

In general, tests should fulfill the following requirements:

  • Predictability
  • Isolation
  • Reliability
  • Fast execution
  • Automation
  • Maintainability

The following describes these requirements.

Predictability

First of all, software tests have to be stable, predictable, and reproducible. The same project circumstances must predictably produce the same test case outcomes, that is, passing or failing. Tests that sometimes pass and sometimes fail are not helpful at all. They either distract developers by providing false positive results or suppress actual bugs with false negative outcomes.

Circumstances that need to be taken into account are, among others, the current time, time zones, locales, randomly generated data, and concurrent execution of other tests...