Book Image

Mastering Hibernate

Book Image

Mastering Hibernate

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)

EJB


If you ever created an EJB application using older versions of JEE specifications, J2EE, you would remember that data persistence was achieved using Entity Beans, which implemented the javax.ejb.EntityBean interface, and you had to implement all those horrifying methods and provide different implementations, depending on the persistence nature of the entity bean, that is container-managed or bean-managed.

Thanks, mostly, to Hibernate, the Java Persistence API (JPA) was born to simplify the implementation. In the next section, we will see how to set up Hibernate as the entity manager when using EJB 3.

Persistence unit

In the JPA world, the Entity Manager represents the persistence unit. It is defined by the javax.persistence.EntityManager interface. This is the JPA API that is your gateway to the persistence store, just as the Hibernate Session is when working directly through the Hibernate API. In EJB3, you will need to declare the persistence unit and let the application server know who...