Before we start wielding JPA and CDI together, let’s get the basics out of the way for JPA. The Java Persistence API allows for the modelling of the domain objects for accessing, persisting, and managing data between POJOs and a relational database. JPA is the standard for working with object-relational mapping (ORM) solutions. Popular ORM solutions include Hibernate, EclipseLink (the reference implementation for all JPA versions), Apache OpenJPA, and DataNucleus. JPA puts the focus back on the domain model for retrieving and persisting data without having to deal with resource management and vendor specific SQL.
Most developers would be accustomed to hearing about Hibernate in articles and projects; it also shows up as a skill sought by employers. While Hibernate and the like can be used directly, using JPA helps us avoid falling in the vendor...