In this Hibernate tutorial, we will build a form with code and assign events. We will then use this form to build queries and add methods. These methods will invoke the appropriate query when the Query button is pressed. Once we have built the form, we will write the code to connect the form to the database.
This Hibernate 3.6 tutorial will introduce you to the various concepts in the framework. It is a lightweight object/relational mapping (ORM) framework that uses the Java Persistence API to map Java classes and data types to SQL data types and provide data query and retrieval facilities.
Entity objects are stored in a database and can be retrieved using various methods. These objects correspond to database records and have a persistent state. However, you can also create and manage objects using Transient objects, which are pushed into Hibernate management. These objects are the equivalent of insert and update actions in the database. In the same way, you can call evict() and clear() to delete an object or remove it from Hibernate’s management.
Another important property to remember is that Hibernate has a deprecated method called HibernateObjectDao(). You can use an enum or a cacheable boolean flag to set this property instead of the old method. Hibernate 3 is Eclipse-based and includes the Spring framework.
The newest version of Hibernate has a bunch of improvements, including improved memory usage and stability. But keep in mind that every update has risks. To avoid problems, testing your project and its dependencies is vital before upgrading it. Hibernate 5.3 offers a good alternative for those using the older versions of this framework.
Hibernate ORM is an object-relational mapping tool. It is available as a Maven artifact. You can download the latest version from Maven Central and JBoss Maven Central. The latest version also includes license detection. This makes it easy to use Hibernate.
Hibernate 3.1.1 is a new version of the Java database framework. It provides a new set of specialized annotations for EJB 3. You can get them from the org. hibernate.annotations package. For instance, the @selectBeforeUpdate annotation specifies that hibernate should never perform an SQL UPDATE without modification. Similarly, the @batchSize annotation defines the number of instances to fetch when fetching the instances.
Hibernate can be used to build a Java-based middle-tier or object-oriented domain model (ODM). Its powerful feature set can simplify translating result sets to a graph of objects. In addition, hibernate’s modular structure helps developers isolate dependencies between different modules and define different ORM features and integration SPIs.
Hibernate also supports a new type of annotation called @GenericGenerator. This annotation can be used in both package and class-level annotations. For example, it will generate a unique constraint for a database table based on the values in a particular property. This annotation can also be used on an association that is marked @NaturalId.
Hibernate uses mapping metadata to define the relationship between Java and SQL data. The mapping file is one such file. For example, an id property is a primary key in an EVENTS table. The id/> element specifies the property’s name, which is the identifier value for that row. Similarly, a generator element tells Hibernate a strategy to get the result set from an SQL query.
In addition, Hibernate allows developers to use association annotations in embeddable objects. Hibernate also supports @MappedSuperclass annotation, which makes superclass properties persistent. Finally, hibernate also provides a specialized annotation named @AssociationOverride, which overrides the association column.
You can easily map a logical view to a corresponding file using Hibernate. Hibernate also integrates the JCache caching specification. In addition, the Hibernate team offers release bundles for download on the SourceForge File Release System. These release bundles contain JAR files, documentation, and source code. It’s an easy way to get started with Hibernate.
EJB3 also allows the mapping of the properties of the target entity. The @MapKey annotation uses the target entity’s primary key as the map key. Normally, this column will be 0, but it’s possible to specify a unique index instead. First, however, it’s important to understand the limitations of this annotation.
Hibernate Annotations are another useful feature of Hibernate. These are used to add persistence metadata and check for constraints. For example, an annotation can be used to express an account balance constraint. Annotations are also used to check whether a constraint is violated. Annotations can be useful when writing complex models that use data from multiple sources.
Immutable annotations can be used in several different ways. For example, an @Immutable annotation can mark an entity or a collection as immutable. In this case, updates to immutable entities will not cause an exception, but deletions will result in HibernateException.