Book Image

Mastering Hibernate

By : Ramin Rad, Koushik Srinivas Kothagal
Book Image

Mastering Hibernate

By: Ramin Rad, Koushik Srinivas Kothagal

Overview of this book

Hibernate has been so successful since its inception that it even influenced the Java Enterprise Edition specification in that the Java Persistence API was dramatically changed to do it the Hibernate way. Hibernate is the tool that solves the complex problem of Object Relational Mapping. It can be used in both Java Enterprise applications as well as .Net applications. Additionally, it can be used for both SQL and NoSQL data stores. Some developers learn the basics of Hibernate and hit the ground quickly. But when demands go beyond the basics, they take a reactive approach instead of learning the fundamentals and core concepts. However, the secret to success for any good developer is knowing and understanding the tools at your disposal. It’s time to learn about your tool to use it better This book first explores the internals of Hibernate by discussing what occurs inside a Hibernate session and how Entities are managed. Then, we cover core topics such as mapping, querying, caching, and we demonstrate how to use a wide range of very useful annotations. Additionally, you will learn how to create event listeners or interceptors utilizing the improved architecture in the latest version of Hibernate.
Table of Contents (16 chapters)

Hibernate Query Language

Hibernate offers its own query language, called HQL, which resembles SQL in many ways but also supports additional features. There are some differences, for example, instead of the table name, you simply use the entity name and Hibernate will figure out the table name. This is because both HQL and JPA Query Language (JPQL) use an object model, and both languages are considered to be object-oriented and support polymorphism and inheritance concepts.

In this section, we'll focus on HQL and also how Hibernate supports native SQL. However, this section is not meant to be a language reference for HQL; this is indeed a powerful language and most likely deserves its own book. For now, it is highly recommended that you read the online documentations for a complete reference.

When composing HQL statements, you should be aware of the following:

  • HQL is case insensitive, except when you are referring to entity classes. It's a convention to use lowercase for all HQL keywords and...