ORM Solutions for Java

From Wiki

This is a list of ORM-frameworks I would consider when starting a new project today.

The list does not claim to be complete. For an alternative list look here.

Most familiar are the mainstream JPA providers :

• Hibernate
• TopLink / TopLink Essentials/ EclipseLink
• KODO / OpenJPA
• JPOX / DataNucleus

There are other, less well known JPA providers:

• Apache Cayenne
• Resin Amber
• CocoBase

Frameworks following another paradigm:

Name	Facts
Carbonado	Persistence abstraction layer for Java applications, providing a relational view to the underlying persistence technology. Entities are defined as interfaces or abstract classes, implementations are generated at runtime. Entities follow the ActiveRecord pattern. UnitOfWork, IdentityMap, DirtyTracking, CascadingPersistence are not supported, OptimisticLocking is supported Querying functionality independent of SQL Supports non-SQL persistence backend (Berkley DB) Relational concepts are not much abstracted (types are object representations of relations, associations are realized with joins based on IDs) Schema-generation is not supported
iBatis	Coupling POJO-objects with SQL statements or stored procedures using a XML descriptor All artifacts (Classes, SQL, XML) are created by the developer. There exist supporting generators. Proven and well documented Versions for Java, .NET and Ruby available
Ebean	Tries to provide a simpler approach to ORM by not using a PersistenceContext DirtyTracking is realized by the entity itself. Mapping annotations are compatible to JPA Supports an OO-Query-API and its own query-language.
activeobjects	Simple persistence solution leaning towards the ActiveRecord pattern. Supports 'no-mapping' approach by relying on conventions. No external dependencies. Easy integration. Advanced schema generation and management via migrations. Relies on SQL for querying.
persist	Minimalistic and simple persistence solution leaning towards the ActiveRecord pattern. Supports 'no-mapping' approach by relying on conventions. No external dependencies. Easy integration. Relies on SQL for querying. Features very limited: associations not supported (at least not documented)?
dreamsource-orm	TODO !
Apache empire-db	TODO !

For the Java-Platform there exist other interesting alternatives:

• JRuby with ActiveRecord
• Groovy with GORM
• History essays from the developers of Java.