Service Data Objects is a technology that allows heterogeneous data to be accessed in a uniform way. The SDO specification was originally developed in 2004 as a joint collaboration between Oracle ( BEA) and IBM and approved by the

Java Community Process The Java Community Process (JCP), established in 1998, is a formalized mechanism that allows interested parties to develop standard technical specifications for Java technology. Anyone can become a JCP Member by filling a form available at thJCP w ...

i
JSR 235
Version 2.0 of the specification was introduced in November 2005 as a key part of the Service Component Architecture.

Relation to other technologies

Originally, the technology was known as Web Data Objects, or WDO, and was shipped in

IBM WebSphere Application Server WebSphere Application Server (WAS) is a software product that performs the role of a web application server. More specifically, it is a software framework and middleware that hosts Java-based web applications. It is the flagship product with ...

5.1 and IBM WebSphere Studio Application Developer 5.1.2. Other similar technologies are JDO, EMF,

JAXB Java XML Binding (JAXB; formerly Java Architecture for XML Binding) is a software framework that allows Jakarta EE, Java EE developers to map Java class (computer science), classes to XML representations. JAXB provides two main features: the abi ...

and ADO.NET.

Design

Service Data Objects denote the use of

language-agnostic Language-agnostic programming or scripting (also called language-neutral, language-independent, or cross-language) is a software paradigm in which no particular language is promoted. In introductory instruction, the term refers to teaching princip ...

data structures that facilitate communication between structural tiers and various service-providing entities. They require the use of a

tree structure A tree structure, tree diagram, or tree model is a way of representing the hierarchical nature of a structure in a graphical form. It is named a "tree structure" because the classic representation resembles a tree, although the chart is genera ...

with a

root node In computer science, a tree is a widely used abstract data type that represents a hierarchical tree structure with a set of connected nodes. Each node in the tree can be connected to many children (depending on the type of tree), but must be con ...

and provide traversal mechanisms (breadth/depth-first) that allow client programs to navigate the elements. Objects can be static (fixed number of fields) or dynamic with a map-like structure allowing for unlimited fields. The specification defines meta-data for all fields and each object graph can also be provided with change summaries that can allow receiving programs to act more efficiently on them.

Developers

The specification is now being developed by IBM,

Rogue Wave Rogue waves (also known as freak waves, monster waves, episodic waves, killer waves, extreme waves, and abnormal waves) are unusually large, unpredictable, and suddenly appearing surface waves that can be extremely dangerous to ships, even to lar ...

, Oracle,

SAP Sap is a fluid transported in xylem cells (vessel elements or tracheids) or phloem sieve tube elements of a plant. These cells transport water and nutrients throughout the plant. Sap is distinct from latex, resin, or cell sap; it is a separ ...

Siebel Siebel was a German aircraft manufacturer founded in 1937 in Halle an der Saale.Gunston p.424 History It originated in the Klemm-Flugzeugwerke Halle that had been founded in 1934 as a branch of Leichtflugzeugbau Klemm in Böblingen. Its nam ...

, Sybase, Xcalia,

Software AG Founded in 1969, Software AG is an enterprise software company with over 10,000 enterprise customers in over 70 countries. The company is the second largest software vendor in Germany, and the seventh largest in Europe. Software AG is traded on t ...

within the OASIS Member Section Open CSA since April 2007. Collaborative work and materials remain on the collaboration platform of Open SOA, an informal group of actors of the industry.

Implementations

The following SDO products are available: *

Rogue Wave Software Rogue Wave Software was an American software development company based in Louisville, Colorado. It provided cross-platform software development tools and embedded components for parallel, data-intensive, and other high-performance computing (HPC ...

HydraSDO * Xcalia (for Java and .Net) * Oracle (Data Service Integrator) , Oracle Data Service Integrator
/ref> * IBM (Virtual XML Garden) * IBM ( WebSphere Process Server) There are open source implementations of SDO from: * The Eclipse Persistence Services Project (

EclipseLink EclipseLink is the open source Eclipse Persistence Services Project from the Eclipse Foundation. The software provides an extensible framework that allows Java developers to interact with various data services, including databases, web services, ...

) * The Apache Tuscany project for Java and C++ * The fcl-sdo library included with

FreePascal Free Pascal Compiler (FPC) is a compiler for the closely related programming-language dialects Pascal and Object Pascal. It is free software released under the GNU General Public License, witexception clausesthat allow static linking against it ...

References

{{reflist

External links

Specification versions and history can be found on * Latest materials a
OASIS Open CSA

Service Data Objects

SDO Specifications at OpenSOA

Introducing Service Data Objects for PHP

Computer networking Java specification requests Persistence Service-oriented (business computing)