In the case of Hibernate, that commercial entity is JBoss
(www.jboss.com), a division of Red Hat (www.redhat.com), they of Linux fame. The commercial
offering of JBoss is 100 percent optional; there are absolutely zero requirements that you pay
one red cent to use Hibernate. However, if you use it in an enterprise setting, you may well
want to pay for the added benefits you get, including a higher level of technical support.
In any case, Hibernate is what??™s known as an Object-Relational Mapping (ORM) tool. An
ORM tool provides a way of mapping relational data stores, a typical relational database for
instance, to object-oriented representations in a typical OOP language, such as Java. With
ORM tools, you create Java (or .NET, in the case of NHibernate, a port of Hibernate to the .NET
Framework) classes, and Hibernate takes care of the database for you. You don??™t think in terms
of tables and other typical database concepts, but just classes.
Hibernate also provides a portable SQL-like language called HQL, short for Hibernate
Query Language, that allows you to query and get back objects (or collections of objects) just
like you would with SQL. This eliminates the differences in SQL dialects that you sometimes
encounter across different database vendors??™ platforms.
Pages:
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784