This chapter introduces EclipseLink. EclipseLink is an advanced, object-persistence and object-transformation framework that provides development tools and run-time capabilities that reduce development and maintenance efforts, and increase enterprise application functionality.
This chapter includes the following sections:
EclipseLink is suitable for use with a wide range of Java Enterprise Edition (Jakarta EE) and Java application architectures. Use EclipseLink to design, implement, deploy, and optimize an advanced object-persistence and object-transformation layer that supports a variety of data sources and formats, including the following:
JPA – For object-relational persistence, supporting the JPA (Jakarta Persistence API) specification and a native API
NoSQL – For object persistence of non-relational NoSQL and EIS databases through JPA and a native API
JAXB – For object-XML transformation, supporting the JAXB (Java Architecture for XML Binding) specification and a native API
JSON – For object-JSON (JavaScript Object Notation) transformation
DBWS – For generation of web services from database tables and stored procedures
The EclipseLink native API includes:
Relational – For transactional persistence of Java objects to a relational database accessed using Java Database Connectivity (JDBC) drivers.
Object-Relational Data Type – For transactional persistence of Java objects to special-purpose structured data source representations optimized for storage in object-relational data type databases such as Oracle Database.
Enterprise information system (EIS) – For transactional persistence of Java objects to a non-relational data source accessed using a Jakarta EE Connector architecture (JCA) adapter and any supported EIS record type, including indexed, mapped, or XML.
XML – For non-transactional, non-prescription (in-memory) conversion between Java objects and XML Schema Document (XSD)-based XML documents using Java Architecture for XML Binding (JAXB).
EclipseLink includes support for EJB 3.0 and the Jakarta Persistence API (JPA) in Jakarta EE and Java SE environments including integration with a variety of application servers including:
Oracle WebLogic Server
Oracle Glassfish Server
JBoss Web Server
IBM WebSphere application server
SAP NetWeaver
Oracle Containers for Jakarta EE (OC4J)
Various other web containers, such as Apache Tomcat, Eclipse Gemini, IBM WebSphere CE, and SpringSource tcServer
EclipseLink lets you quickly capture and define object-to-data source and object-to-data representation mappings in a flexible, efficient metadata format.
The EclipseLink runtime lets your application exploit this mapping metadata with a simple session facade that provides in-depth support for standard APIs such as JPA, and JAXB as well as EclipseLink-specific extensions to those standards.
EclipseLink is the reference implementation of the Java Persistence Architecture (JPA) 2.0 specification It also includes many enhancements and extensions.
This document explains the EclipseLink enhancements and extensions to JPA. Please refer to the JPA specification for full documentation of core JPA. Where appropriate, this documentation provides links to the pertinent section of the specification.
For more information, see:
Java Persistence specification for complete information about JPAhttp://jcp.org/en/jsr/detail?id=317
EclipseLink Documentation Center for more information about EclipseLink support of JPA. http://www.eclipse.org/eclipselink/documentation/
The EclipseLink API reference documentation (Javadoc) for complete information on core JPA plus the EclipseLink enhancementshttp://www.eclipse.org/eclipselink/api/
The schema for the JPA persistence configuration filehttp://java.sun.com/xml/ns/persistence/persistence_2_0.xsd
The schema for the persistence object/relational mapping filehttp://java.sun.com/xml/ns/persistence/orm_2_0.xsd
The schema for the native EclipseLink mapping filehttp://www.eclipse.org/eclipselink/xsds/eclipselink_orm_2_0.xsd
Examples that display the use of a number of EclipseLink JPA featureshttp://wiki.eclipse.org/EclipseLink/Examples/
JavaEE and JPA tutorial. Although this tutorial does not include EclipseLink-specific information, it does contain useful information to help you implement JPA 2.0 applications. http://download.oracle.com/javaee/5/tutorial/doc/bnbpy.html
Java Persistence, a wiki-based "open book" about JPA 2.0http://en.wikibooks.org/wiki/Java_Persistence