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
About the Author
About the Reviewer
Customer Feedback
Appendix: Links and further resources

What to test

Before we go into the topic of how to craft effective, fast, reliable, automated, and maintainable test cases, let's have a look at what assets to test. There are tests on a code layer as well as end-to-end tests. Code layer tests are based on the project's source code and are usually executed during development and build time, whereas end-to-end tests, of all kinds, operate on a running application.

Depending on the test scopes, which we will get to know in the next section, there are different layers of tests, whether tests operate on classes, multiple components, enterprise applications, or whole environments. In all cases the test object needs to be isolated from external concerns. The nature of tests is that they verify certain behavior under specific conditions. The environment surrounding the test object, such as the test cases as well as used components, have to interact with the test object accordingly. The test case will therefore control the test object. This not only...