Empty query

The EmptySparqlRequest specifies an empty request, which is guaranteed to return non result regardless of the Ontology.

The request has the following content:

   SELECT *
   WHERE {
      ?o rdf:type owl:Thing .
   }
   LIMIT 0

To create an empty request, you can use one of the following constructors:

• The EmptySparqlRequest() create an empty request without prefixes
• The EmptySparqlRequest(char prefixInclusionType) creates an empty request with or without prefixes depending on the prefixInclusionType value^[1]
  See

For example suppose the following code:

   EmptyRequest request = new EmptyRequest();
   String sparql = request.getSPARQL();

The result will be:

   SELECT *
   WHERE {
      ?o rdf:type owl:Thing .
   }
   LIMIT 0

Invalid request

The InvalidSparqlRequest specifies an invalid request, which is also guaranteed to return non result regardless of the Ontology. The only difference with an empty request is that the InvalidSparqlRequest.isWellFormed() returns false.

For example suppose the following code:

   InvalidSparqlRequest request = new InvalidSparqlRequest();
   String sparql = request.getSPARQL();

The result will be:

   SELECT *
   WHERE {
      ?o rdf:type owl:Thing .
   }
   LIMIT 0