In part 1 we’ll show you why object persistence is such a complex topic and what solutions you can apply in practice. Chapter 1 introduces the object/ relational paradigm mismatch and several strategies for dealing with it, foremost object/relational mapping (ORM). In chapter 2, we’ll guide you step by step through a tutorial with Jakarta Persistence API (JPA), Hibernate, and Spring Data—you’ll implement and test a “Hello World” example. Thus prepared, in chapter 3 you’ll be ready to learn how to design and implement complex business domain models in Java, and which mapping metadata options you have available. Then chapter 4 will examine working with Spring Data JPA and its features.
After reading this part of the book, you’ll understand why you need ORM and how JPA, Hibernate, and Spring Data work in practice. You’ll have written your first small project, and you’ll be ready to take on more complex problems. You’ll also understand how real-world business entities can be implemented as Java domain models and in what format you prefer to work with ORM metadata.