The OneToMany and ManyToOne annotations are two major JPA annotations that are used for defining two different kinds of associations. The OneToMany annotation define a many-valued association with one-to-many multiplicity, whereas the ManyToOne annotation defines a single-valued association to another entity that has many-to-one multiplicity. The Multiplicity concept seems ambiguous, but it simply tells you the …
EclipseLink
EclipseLink Tutorials
EclipseLink is reference implementation for the Java Persistence API (JPA) specification. This project is maintained and supported by the Eclipse Open Source foundation. EclipseLink not only supports the JPA standards, it also supports the following open source standards: Java Persistence API (JPA) Java Architecture for XML Binding (JAXB) Java Connector Architecture (JCA) Service Data Objects …
EclipseLink / JPA Annotations – @OneToOne
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 …
EclipseLink / JPA – com.mysql.jdbc.exceptions.jdbc4.MySQLSyntaxErrorException: Unknown column
This post explains the common exception thrown in your eclipselink or JPA program when you miss the @JoinColumn annotation to refer the foreign key value. @JoinColumn is very important, cause it is used to indicate that there is a Joining at the annotated property, where the persistence implementation will take care of and consider the …
EclipseLink – JPA Annotations
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 …
EclipseLink – JPA Fields Annotations – @Basic and @Transient
As mentioned earlier, EclipseLink – JPA is a persistence service, provides a mechanism to communicate with a different database vendors. That type of communication has been achieved through what has become known as annotation-based configuration, which is considered as an alternative way for doing a configuration rather than the XML. The XML-based configuration remains one …
EclipseLink – Configuration error. Class [com.mysql.jdbc.Driver] not found [javax.persistence.PersistenceException]
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 …