JPA

In the Java Persistence API (JPA) The entities support inheritance, polymorphic, polymorphic associations, and polymorphic queries. Both abstract and concrete classes can be entities, and both of them can be annotated with the @Entity annotation, mapped as entities and queried for as entities. Entities can extend non-entity classes and non-entity classes can extend entity classes, so …

The Many-To-Many annotation is one of the most important annotations provided by the EclipseLink – JPA. It defines a many-valued association with ManyToMany multiplicity (See single-valued multiplicity and different kind of many-valued multiplicity). A newly concept has introduced such as (JoinTable) as well as a new annotation like (@JoinTable) when we are coming to introduce …

OneToOne annotation is one of the annotations that are used for defining a single-valued association to another entity that has one-to-one multiplicity. The multiplicity concept seems ambiguous but it simply tells you the maximum and minimum allowed members of the set. It is a UML design concept for defining the association relationship, in one-to-one case …

Have you ever been standing up close to an article that list most of the annotations that are used by the EclipseLink – JPA API? The EclipseLink provides many annotations covering the persistence into databases. But when we are coming into use of these annotations, we have already faced a big obstacles while remembering those …

This post provides possible exception while doing the JPA programming and the suggested solution for resolving the exception. This post will solve the issue that can be happened while the JPA implementation trying to get a persistence provider. The exception explained in this post thrown when you have not configured properly the persistence unit name in …

The EclipseLink – JPA API is persistence service that provided a standard way to communicate with the database. The major important issue needs to take care of while development of a project using a JPA, is a database driver that can help the JPA communicates with the suggested database. This post will cover a proper …