How To Provide A SPARQL Endpoint Using Tomcat 7.0.27

Question

So I got this webapp running on a tomcat 7.0.27 which manages a large RDF/Ontology model with Jena, and what I want to do is provide a SPARQL endpoint to enable clients to query this model.
Currently, there's a SOAP webservice where a SPARQL query can be embedded in a (SOAP) message, which is a legacy implementation I'm supposed to modernize.

How does one go about providing a SPARQL endpoint? It seems just an empty buzzword to me. What's the difference between a (SOAP) webservice and a SPARQL endpoint? I've been reading about Joseki and ARQ, which apparently (in combination?) provide SPARQL endpoint functionality, but I'm not sure whether I need it, since most people who are talking about it on the web are using older tomcat versions (5/6).
Can somebody explain to me how to provide a SPARQL endpoint or nudge me in the right direction in terms of further resources?

Broucek

Answer 1

Tomcat is just a servlet container. It runs web applications. A SPARQL endpoint is a particular kind of web application that you can run in Tomcat.

Fuseki (the successor to Joseki, and, like Tomcat, a project of the Apache Software Foundation) is the most popular choice.

You say that your RDF model is “large”. Depending on how large it is (that is, does it comfortably fit in memory or not?) you may need a persistent RDF store as well, such as Apache TDB (which is designed to work with Fuseki) or OpenLink Virtuoso (which is its own webserver, so you wouldn't use it together with Tomcat and Fuseki but as a standalone server).

Overbold

Thanks for a very clear answer. So it seems Fuseki should be integrated with my running Tomcat 7 setup, is that correct? The model will actually fit in memory, so that's ok. – Broucek

There is still an open (and relevant to this question) issue: JENA-201 (issues.apache.org/jira/browse/JENA-201) which is about delivering Fuseki as a WAR file (so that it's easy to deploy in servlet containers such as Apache Tomcat). Help welcome! ;-) – Noami

In that case let me just plug OpenRDF Sesame (openrdf.org) as an alternative, since it is already distributed as a war and developed for use with Apache Tomcat. – Tao