DB Objects for Java - Lightweight and flexible solution for storing and retrieving java objects into and from relational databases, without using SQL. [Open source, LGPL] Osage - Object-Relational mapping for JDBC databases, with XML features. [Open Source, LGPL] CocoBase Enterprise O/R - Object/Relational mapping tool, with customized mappings for each major EJB server (including JBoss). [Commercial] jRelationalFramework - A lightweight framework that was written to automate the most tedious 80% of relational database access coding and leave the other 20% to the developer. [Open Source, MPL] jStorm - Simple tool for object-relational mapping, based on DbObjects, with mechanisms for aggregation and concurrency stamps. [Open Source, GPL] Abra - A Java library and a set of tools that can be used for storing and retrieving Java objects in a relational database. [Open source, BSD license] J-Database Exchange (JDX) - A cross-platform solution for transactional persistence of Java objects . By Software Tree, Inc. [Commercial] Apache ObJectRelationalBridge - OJB - A framework that provides transparent persistence of Java objects for JDBC-compliant RDBMS. Implements ODMG 3.0, JDO and uses XML-based O/R Mapping. [Open Source, LGPL] Torque - An XML-based persistence layer. Part of the Apache Jakarta family. [Open Source, BSD-like] CarrierWave - Provides the following features: build generated client side data objects structurally mirroring server side business objects; pluggable persistence; pluggable binding between client and server; pluggable query mechanism; zero-configuration externalization and internalization of server state into and from XML. [Open source, GPL] JDBM - A simple transactional persistence engine for Java. It can used to store a mix of objects and BLOBs, and all updates are done in a transactionally safe manner. JDBM also provides scalable data structures, such as HTree and B+Tree, to support persistence of large object collections. [Open source, BSD License] FormPers - A persistence framework with forms automation. It support on-the-fly SQL table creation/structure modification base on definition in Java class, automated form creation and automated form result parsing. [Freeware] DB Visual Architect - An Object-Relational mapping tool. Generate persistent enable Java source from Class Diagram or ERD. A diagram editor is provided. It can generate code for client applications and server side applications. [Commercial] iBatis - XML-based Object/Relational mapping and persistence framework as well as a data access abstraction layer. [Open source] Object-Relational Mapping - Information and facts about object-relational mapping products, architecture problem-solving, and direction in product comparison and selection. JORM (Java Object Repository Mapping) - The ObjectWeb open source adaptable persistence service. It is used to offer CMP 2.0 for the JOnAS server, as well as Speedo, a JDO implementation. [Open source, LGPL] SimpleORM - Implement, low overhead object/relational mapping on top of Java JDBC. [Open source] Cayenne - An Object-Relational mapping framework working with relational databases. [Open Source] JGrinder - Initially began as a solution for Object/Relational persistence. Supporting this involved the creation of many utility classes and tools that could be used to accelerate any application development effort. [Open source, LGPL] ONJava.com: Don't Let Hibernate Steal Your Identity - Typical means of establishing uniqueness and identity in databases, and thus Hibernate, don't necessarily suit Java's identity-oriented equals() and hashCode() methods. James Brundege has another idea for how to solve this problem. ONJava.com: Object-Relational Mapping with Apache Jakarta OJB - Charles Chan demonstrates OJB, an open source Java object persistence framework. Objective database abstraction layer (ODAL) - A database persistence framework including query API, ORM, data validation/conversion, stored procedure support, code generation. Download and documentation are offered. [Open source, LGPL] EclipseLink - ORM project from Eclipse (Oracle, Sun). Provides ORM, JPA, OXM, JAXB, SDO, WebServices, EIS. JPA 2.0 reference implementation, JPA provider of Oracle WebLogic, Sun Glassfish. [Open source, EPL] Java Persistence - Wikibook on JPA, and Java persistence from Wikimedia Wikibooks. Hibernate ORM framework - Hibernate an open source Java persistence framework project. Perform powerful object relational mapping and query databases using HQL and SQL. [Open source, LGPL] JavaRanch - Object Relational Mapping - JavaRanch Big Moose Saloon forum for object relational mapping. Ammentos - A lightweight persistence framework for Java (JDK5 or later). [Open source, GPL]