DataNucleus is an open source

Open-source software

Open-source software is computer software that is available in source code form: the source code and certain other rights normally reserved for copyright holders are provided under a software license that permits users to study, change, improve and at times also to distribute the software.Open...

 project (under the Apache 2 license) which provides a series of software products around data management in Java

Java (programming language)

Java is a programming language originally developed by James Gosling at Sun Microsystems and released in 1995 as a core component of Sun Microsystems' Java platform. The language derives much of its syntax from C and C++ but has a simpler object model and fewer low-level facilities...

.

DataNucleus Access Platform is a fully compliant implementation of the Java Data Objects

Java Data Objects

Java Data Objects is a specification of Java object persistence. One of its features is a transparency of the persistent services to the domain model. JDO persistent objects are ordinary Java programming language classes ; there's no requirement for them to implement certain interfaces or extend...

 (JDO) 1.0, 2.0, 2.1, 2.2, 3.0 specifications and the Java Persistence API

Java Persistence API

The Java Persistence API, sometimes referred to as JPA, is a Java programming language framework managing relational data in applications using Java Platform, Standard Edition and Java Platform, Enterprise Edition....

 1.0, 2.0 specifications, providing transparent persistence

Persistence

Persistence may refer to:* Image persistence, in LCD monitors* Multidrug tolerance, a dormant, persistent state of a bacterial population* Persistence , the characteristic of data that outlives the execution of the program that created it...

 of Java

Java (programming language)

Java is a programming language originally developed by James Gosling at Sun Microsystems and released in 1995 as a core component of Sun Microsystems' Java platform. The language derives much of its syntax from C and C++ but has a simpler object model and fewer low-level facilities...

 objects. It supports persistence to the widest range of datastores of any Java persistence software, supporting all of the main object-relational mapping

Object-relational mapping

Object-relational mapping in computer software is a programming technique for converting data between incompatible type systems in object-oriented programming languages. This creates, in effect, a "virtual object database" that can be used from within the programming language...

 (ORM) patterns, allows querying using either JDOQL, JPQL or SQL

SQL

SQL is a programming language designed for managing data in relational database management systems ....

, and comes with its own byte-code enhancer. It allows persistence to relational datastores (RDBMS), object-based datastores (db4o

Db4o

db4o is an embeddable open source object database for Java and .NET developers. It is developed, commercially licensed and supported by Versant....

, NeoDatis ODB

NeoDatis ODB

NeoDatis ODB is an object database available the GNU Lesser General Public License, hence usable in free or commercial applications. NeoDatis ODB is available both for Java and .NET, the latter being still under development.-Features:...

), document-based storage(XML

XML

Extensible Markup Language is a set of rules for encoding documents in machine-readable form. It is defined in the XML 1.0 Specification produced by the W3C, and several other related specifications, all gratis open standards....

, Excel

Microsoft Excel

Microsoft Excel is a proprietary commercial spreadsheet application written and distributed by Microsoft for Microsoft Windows and Mac OS X. It features calculation, graphing tools, pivot tables, and a macro programming language called Visual Basic for Applications...

, OpenDocument spreadsheets

OpenDocument

The Open Document Format for Office Applications is an XML-based file format for representing electronic documents such as spreadsheets, charts, presentations and word processing documents....

), web-based storage (JSON

JSON

JSON , or JavaScript Object Notation, is a lightweight text-based open standard designed for human-readable data interchange. It is derived from the JavaScript scripting language for representing simple data structures and associative arrays, called objects...

, Google Storage

Google Storage

Google Cloud Storage is a RESTful online storage web service for storing and accessing your data on Google's infrastructure. The service combines the performance and scalability of Google's cloud with advanced security and sharing capabilities...

, Amazon Simple Storage Service), map-based datastores (HBase

HBase

HBase is an open source, non-relational, distributed database modeled after Google's BigTable and is written in Java. It is developed as part of Apache Software Foundation's Apache Hadoop project and runs on top of HDFS , providing BigTable-like capabilities for Hadoop...

, Google's BigTable

BigTable

BigTable is a compressed, high performance, and proprietary database system built on Google File System , Chubby Lock Service, SSTable and a few other Google technologies; it is currently not distributed nor is it used outside of Google, although Google offers access to it as part of their Google...

), document stores (MongoDB

MongoDB

MongoDB is an open source, high-performance, schema-free, document-oriented database written in the C++ programming language...

) as well as other types of datastores (LDAP). It is designed using OSGi

OSGi

The Open Services Gateway initiative framework is a module system and service platform for the Java programming language that implements a complete and dynamic component model, something that does not exist in standalone Java/VM environments...

 technology.

DataNucleus Access Platform is the persistence layer behind Google App Engine

Google App Engine

Google App Engine is a platform as a service cloud computing platform for developing and hosting web applications in Google-managed data centers. It virtualizes applications across multiple servers,...

 for Java, and VMForce (cloud offering from Salesforce.com

Salesforce.com

Salesforce.com is an enterprise cloud computing company headquartered in San Francisco that distributes business software on a subscription basis. Salesforce.com hosts the applications off-site...

 and VMWare

VMware

VMware, Inc. is a company providing virtualization software founded in 1998 and based in Palo Alto, California, USA. The company was acquired by EMC Corporation in 2004, and operates as a separate software subsidiary ....

).

External links

• DataNucleus - Open Source Java data management software
• DataNucleus Access Platform - an Open Source Java persistence implementation
• DataNucleus Access Platform Project Documentation