Java Persistence APIs
These are the APIs and abstractions defined by the framework which can be used Java application irrespective of the database used.
- Defines how the data in the database are converted to and from Java objects.
- APIs to perform actions on the database.
ORM - Object-Relational Mapping
ORM aims to simplify database interactions by providing an abstraction layer that translates between objects and database tables. It enables developers to work with databases using the same language as the rest of their application.
Hibernate and Eclipselink are examples of such ORM libraries. They implement JPA specifications.
Spring Data
Spring Data library doesn't implement JPA specifications. Instead it only writes wrappers on JPA specifications which avoids writing boiler plate code for standard CRUD methods.
For the repositories which we create by extending JpaRepository and JpaSpecificationExecutor interfaces, all queries are automatically added during compile time.
Repository interface is an example which automatically generates a lot of methods automatically.
