RDF2Go
From semanticweb.org
| RDF2Go | |
|---|---|
 | |
| rdf2go.semweb4j.org/ | |
| Status: | stable |
| Last release: | 4.7.0 (Jan 5, 2009) |
| License: | BSD |
| Affiliation: | FZI |
RDF2Go is an abstraction over triple (and quad) stores. It allows developers to program against rdf2go interfaces and choose or change the implementation later easily.
Contents |
[edit] About
The three main features of RDF2Go are:
- Program now, decide on triple store later - triple-centric API
- Easy to extend - only a few simple methods have to be implemented by a triple (or quad) store
- Triple and quad support - All techniques are available for triple and quad models
RDF2GO is released under the new BSD license. Alternative licensing is possible, just ask us. The project is funded by the European projects Knowledge Web and NEPOMUK.
- Bookmark-URL: http://rdf2go.semweb4j.org (this page)
- Download releases from directory
- For changelog, please consult the module-changelogs
See also: RDF2Go on Ohloh
[edit] Modules
RDF2Go consists of several parts that together make up the distribution. The JARs are named org.semweb4j.* and the Java packages in the JARs are still named org.ontoware.* to maintain compatibility with existing deployments.
In previous versions of RDF2Go there was a YARS adapter which is no longer maintained due to lack of time. Do you want to help out? Contact us!
Note: As of RDF2Go 4.7.0 the module structure has been simplified. There are now only these modules, that are relevant:
[edit] API (rdf2go.api)
The API, the base implementation classes. And utility classes running on top of any adapter. This contains e.g. the RDFTool class developed by DFKI.
- Maven reports including links to JavaDocs, changelog, source code as HTML, JUnit test results, developer team, dependencies, list of open TODO tags in the code, ...
- Releases (consider downloding the distribution instead)
- Anonymous Subversion (use https:// for developer access)
[edit] Test helper (rdf2go.impl.base.test)
The abstract base classes for tests. These need to be in their own project to keep the API jar lean and allow other projects to re-use this code for their tests. This follows Maven and OSGI packaging guidelines.
- Maven reports including links to JavaDocs, changelog, source code as HTML, JUnit test results, developer team, dependencies, list of open TODO tags in the code, ...
- Releases (consider downloding the distribution instead)
- Anonymous Subversion (use https:// for developer access)
[edit] Jena Adapter (rdf2go.impl.jena24)
Implements the API and extends the impl.base classes. Delegates all calls to a Jena 2.4 model. This adapter provides only a Model implementation, no ModelSet, as Jena has no support for quads. (The new SDB or NG4J extensions have not been used due to lack of time, feel free to help out)
- Maven reports including links to JavaDocs, changelog, source code as HTML, JUnit test results, developer team, dependencies, list of open TODO tags in the code, ...
- Releases (consider downloding the distribution instead)
- Anonymous Subversion (use https:// for developer access)
- Status: up-to date with RDF2Go 4.6 API
[edit] Sesame 2.0 Adapter (rdf2go.impl.sesame20, former: openrdf-rdf2go)
Implements the API and extends the impl.base classes. Delegates all calls to a Sesame 2.0.1 repository. This adapter provides a Model and a ModelSet implementation.
- Maven reports including links to JavaDocs, changelog, source code as HTML, JUnit test results, developer team, dependencies, list of open TODO tags in the code, ...
- Releases (consider downloding the distribution instead)
- Anonymous Subversion (use https:// for developer access)
- Status: up-to date with RDF2Go 4.6 API
[edit] Sesame 2.2 Adapter (rdf2go.impl.sesame22)
Implements the API and extends the impl.base classes. Delegates all calls to a Sesame 2.2.3 repository. This adapter provides a Model and a ModelSet implementation.
- Maven reports including links to JavaDocs, changelog, source code as HTML, JUnit test results, developer team, dependencies, list of open TODO tags in the code, ...
- Releases (consider downloding the distribution instead)
- Anonymous Subversion (use https:// for developer access)
- Status: up-to date with RDF2Go 4.7 API
[edit] Distribution (rdf2go.dist)
This is a simple maven project that helps to create a complete distribution. It's mainly a pom.xml file with dependencies to other rdf2go parts.
[edit] Documentation and Tutorial
- Lesson 1 - 4 - Introduction (maybe slightly outdated)
- FAQ - Frequently asked questions
- RDF2Go/CodeSamples
- User Guide and FAQ
- RDF2Go/Building From Source
- Binding explained - RDF2Go has several ways to configure which triple store driver (aka adapter) to use.
- A deliverable that describes RDF2GO can be found here.
- RDF2Go at ontoware.org (outdated)
- Comparing RDF2Go to other approaches (outdated)
- How to write a RDF2GO adapter for your triplestore (outdated)
- Configuration of Triplestore Adapters with Property-Files (outdated)
Related Projects
- To generate domain-specific Java classes you can use RDFReactor, RDF2Java or other projects mentioned on Tripresso.
[edit] Road Map
For future versions suggested changes are:
- Cleaner SPI interface (API is for users, SPI is for those people implementing the adapters)
[edit] Contact, Feedback, Help
- new Semweb4j Google Group - the best place to ask for help
- old Developer mailing list including archives
- Issue tracker
Acknowledgements
- Initial idea: User:Max Völkel
- Coding, testing, debugging: User:Max Völkel, Benjamin Heitmann, Werner Thiemann, Sebastian Gerke, Leo Sauermann
- European Projects supporting this research: Knowledge Web, Nepomuk
[edit] Who uses RDF2GO?
- RDFReactor - Object-oriented RDF access in Java, no RDF knowledge required at all (but an RDF Schema)
- SemVersion - Versioning for RDF
- Aperture - extracting and querying full-text content and metadata from various sources
- Hyena - Universal RDF editor
- NEPOMUK
- SemFS
- Theseus, in basic technologies, ontologies
[edit] How to use RDF2Go as a Semantic Web developer
Example for the 4.3 - 4.6 release
public static void main(String[] args) throws ModelException {
// getting model
Model model = RDF2Go.getModelFactory().createModel();
model.open();
// creating URIs
URI max = model.createURI("http://xam.de/foaf.rdf.xml#i");
URI currentProject = model.createURI("http://xmlns.com/foaf/0.1/#term_currentProject");
URI name = model.createURI("http://xmlns.com/foaf/0.1/#term_name");
URI semweb4j = model.createURI("http://semweb4j.org");
// adding a statement to the model
model.addStatement(max, currentProject, semweb4j);
model.addStatement(max, name, "Max Völkel");
// dumping model to the screen
model.dump();
// query model for all names of max
for(Statement stmt : model.getStatement(max,name, Variable.ANY) ) {
// do something
System.out.println( stmt.getObject() );
}
}
[edit] How to contribute to RDF2Go
It's a good idea to first announce on the list, what you want to do, to avoid duplicate work. Check out the latest trunk, make your changes and create a patch (in Eclipse: choose 'project' scope, not 'workspace'). Email the patch to Max Völkel and get it applied. Or even better: attach it to a JIRA bug tracker issue.
