Tools

Apache Jena Command Line Tools

Jenas command line tools are a collection of Shell scripts/Batch scripts that allow to access functionalities of that RDF/OWL programming library without composing Java programs. For the excercises proposed, usage will probably be limited to the tool that reads Turtle RDF documents to either validate them syntactically or to convert them to another RDF serialisation format. (turtle/ turtle.bat).

Fuseki SPARQL Server

Fuseki allows to query and update configured RDF datasets using SPARQL queries. It also offers a browser-based application to formulate and execute SPARQL queries with syntax highlighting and hints for syntactic error in entered queries.

You find a copy of Fuseki pre-configured for the excercises in tools/fuseki. To start it, oben a new terminal window, navigate to that directory and run the start script ./fuseki-server (Linux/Mac) or .\fuseki-server.bat (Windows). The command prompt will remain occupied by the server process during execution and log messages about the initlization process, received queries etc. will be printed. To terminate the server process, send SIGINT by pressing CTRL +C in the terminal with the server process running.

Once Fuseki has been started, you can visit http://localhost:3030/dataset.html to access the graphical SPARQL user interface. Ensure that the appropriate dataset for the excercise you intend to tackle is selected in the ‘Dataset’ drow-down menu at the top. (/wilde for Excercise A, /brown for Exercise B).

LodLive Web of Data Browser

LodLive is a Javascript-based browser application that allows stepwise exploration of RDF knowledge graphs. A copy of LodLive slightly modified and pre-configured for this session is located in the tools/lodlive directory.

To lauch, open the app_en.html start page in that directory in your browser. When invoking this HTML document without additional query parameters in the URL, you will be presented with a start screen. The boxes in the lower row in light green represent the configured local datasets. With the contained dropdown menus you can select example resources to start a browsing session. If you already know a specific resource IRI you would like to use as starting point, you can either enter it in the blue box on the start screen or add it to the URL presented in the navigation bar of your browser:

file://$MATERIALS_ROOT/tools/lodlive/app_en.html?$RESOURCE_IRI

When after selecting your entry resource, you will see the actual graph exploration view with the representation of the selected resource as first circle in the center of the viewport. Although usage for further exploration is quite intutive, please consider opening and skimming the in-app explanation offered by buttons on the left side of the viewport.

Note

LodLive retrieves the statements to describe and visualise resources from the local Fuseki SPARQL Server, so please ensure that it is up and running before using LodLive.