Package net.sf.mmm.persistence.api

Provides the API for a persistence layer.

See: Description

Interface Summary

Interface	Description
GenericDao<ID,ENTITY extends GenericEntity<ID>>	This is the interface for a Data Access Object (DAO).
PersistenceManager	This is the interface for a manager of the persistence layer.
RevisionedDao<ID,ENTITY extends RevisionedEntity<ID>>	This is the interface for a GenericDao with the ability of revision-control.
RevisionedPersistenceManager	This is the interface for a PersistenceManager with the ability of revision-control (auditing), e.g.
RevisionMetadata	This is the interface for the metadata associated with a historic revision of an entity.

Exception Summary

Exception	Description
PersistenceException	This is the abstract base-class for all exceptions defined by this persistence API.

Package net.sf.mmm.persistence.api Description

Provides the API for a persistence layer.

Persistence API

This package contains the API for a persistence layer.
ATTENTION:
This is not yet another O/R mapper or java persistence API (JPA) wrapper!
The purpose of this API and its implementations is to help you writing a structured and well designed persistence layer. The JPA is a perfect API for the O/R mapping of your entities to a database. However, for any reasonable business application you need to write a custom persistence layer on top of the JPA with your entities, queries, data access objects (DAOs), etc.
To support you with the design of your persistence layer this API and its basic implementations will help you. If you do not like dependencies on this code feel free to copy the ideas of this design into your own code.

A major principle of this API is to establish a uniform structure as well as generic access for your entities and DAOs. All your entities shall therefore implement the interface GenericEntity and all your DAOs the interface GenericDao. The overall entry point is PersistenceManager.
For revisioning/auditing support there are also Revisioned* extensions of the interfaces like RevisionedPersistenceManager.
NOTE:
After this code has been created we noticed the existence of spring-data-jpa. This is a similar approach that you can choose alternatively. However, it is doing a lot of magic. Therefore, we decided to continue with our approach. You should also be aware that there are also additional features not offered by spring-data.