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)

Pagination


Paginating through search data is a very common functionality in most enterprise applications. Luckily, Hibernate provides several ways of paginating through the data. One efficient way of doing this is by using the criteria objects that were discussed earlier.

Usually, pagination is accompanied by sorting the search results. The following example shows how this is done using the criteria API:

Criteria criteria = session.createCriteria(Person.class);
List<Person> persons = criteria
  .addOrder(Order.asc("lastname"))
  .setFirstResult(75)
  .setMaxResults(20)
  .list();

Hibernate (actually, the database dialect) composes the SQL to limit the result set to your max result, starting from the offset:

select <columns>
from
Person this_ 
left outer join
Address addresses_ 
    on this_.id=addresses_.person_id 
order by
       this_.lastname asc limit ? offset ?

It is important to know that different database engines implement limit differently. The performance of your query can...