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)

Events


As discussed in Chapter 1, Entity and Session, almost every action in the persistence context is translated into an event. This includes events such as load, save, merge, lock, and flush. For a complete list of events in Hibernate, you should look at the JavaDoc for org.hibernate.event.spi.EventType.

Every event in Hibernate has a corresponding listener that acts when the event is fired. The Hibernate event architecture uses the Service Provider Interface model to discover event listeners. This allows you to plug in your own listener for a certain event. In this section, we will show you how to write event listeners.

Event listener

Hibernate defines the event contract using the listener interfaces (refer to org.hibernate.event.spi) and it provides a default implementation for each event (see org.hibernate.event.internal). Through the service provider interface, you can append additional listeners. Keep in mind that event listeners are considered singletons, so they are not thread-safe...