Although the Greek philosopher Heraclitus wasn’t well known as a software developer, he seemed to have a good handle on the subject. He has been quoted as saying, The only constant is change. That statement captures a foundational truth of software development. Spring Boot autoconfiguration has dramatically reduced the amount of explicit configuration (whether with XML or Java) required to build an application. In fact, by the time you finish the example in this chapter, you’ll have a working Spring application that has only a single line of Spring configuration code!

Chapter 1 introduces Spring and Spring Boot and how to initialize a Spring project. In this chapter, you’ll take the first steps toward building a Spring application that you’ll expand upon throughout the course of the book. Craig Walls is an engineer at VMware, a member of the Spring engineering team, a popular author, and a frequent conference speaker. It provides a Maven goal that enables you to run the application using Maven. You’ll try out this goal in section 1.3.4.Chapter 6 expands on the discussion of Spring MVC started in chapter 2 by looking at how to write REST APIs in Spring. Java-based configuration offers several benefits over XML-based configuration, including greater type safety and improved refactorability. Even so, explicit configuration with either Java or XML is only necessary if Spring is unable to automatically configure the components. Next, take note of the element and, more specifically, its child. This specifies that your project has spring-boot-starter-parent as its parent POM. Among other things, this parent POM provides dependency management for several libraries commonly used in Spring projects. For those libraries covered by the parent POM, you won’t have to specify a version, as it’s inherited from the parent. The version, 2.0.4.RELEASE, indicates that you’re using Spring Boot 2.0.4 and, thus, will inherit dependency management as defined by that version of Spring Boot. In general, developers new to Spring should start with chapter 1 and work through each chapter sequentially. Experienced Spring developers may prefer to jump in at any point that interests them. Even so, each chapter builds upon the previous chapter, so there may be some context missing if you dive into the middle of the book. About the code TacoCloudApplication.java—This is the Spring Boot main class that bootstraps the project. We’ll take a closer look at this class in a moment.

Spring in Action, 5th edition is for Java developers who want to get started with Spring Boot and the Spring Framework as well as for seasoned Spring developers who want to go beyond the basics and learn the newest features of Spring. How this book is organized: a roadmap

about the book

The only book you’ll ever need to learn and master the Spring ecosystem. This update is a must-read.