Preface

This is our third book about Hibernate, an open source project that is almost 15 years old. In a recent poll, Hibernate was among the top five tools used by many Java developers every day. This shows that SQL databases are still the preferred technology for reliable data storage and management, especially in the Java enterprise software development space. It’s also a testament to the quality of specifications and tools available, which today make it easy to start a project and to estimate and reduce risk when building large, complex applications.

The fifth major Hibernate release is now available, as well as the second major version of the Java Persistence API specification (JPA) implemented by Hibernate. The core of Hibernate, or what is now called object/relational mapping (ORM), has been mature for a long time, and many small improvements have been made over the years. Other related projects such as Hibernate Search, Hibernate Bean Validation, and more recently Hibernate object/grid mapping (OGM) are delivering new and innovative solutions that make Hibernate a complete tool kit for a diverse range of data-management tasks.