In my previous post, Using Jena and SHACL to validate RDF Data, I have looked at how RDF data can be validated using SHACL. A closely related concern to that of constraints checking, is rule execution, for which SHACL can also be used.

A SHACL Rule Example

We will again use an example from the SHACL specification. Assume we have the a file rectangles.ttl that contains the following data:

rectangles.ttl

Assuming we want to infer that when the height and width of a rectangle are equal, the rectangle represents a square, the following SHACL rule specification can be used (which we will store in rectangleRules.ttl):

rectangleRules.ttl

A Code Example using Jena

Naturally you will need to add SHACL to your Maven pom dependencies. Then the following code will execute your SHACL rules:

SHACL rule execution using Jena

Running the Code

Running the code will cause an inferences.ttl file to be written out to $Project/src/main/resources/. It contains the following output:

inference.ttl

Note that ex:InvalidRectangle has been ignored because it does not adhere to sh:condition ex:Rectangle, since it does not have ex:height and ex:width properties. Also, ex:NonSquareRectangle is a rectangle, not a square.

Conclusion

In this post I gave a brief overview of how SHACL can be used to implement rules on RDF data. This code example is available at shacl tutorial.