code: private void deleteGraphSparqlUpdate(URI graphUri) {
          UpdateRequest request = UpdateFactory.create();
          request.setPrefixMapping(PrefixMapping.Factory.create().setNsPrefixes(Vocabularies.prefixes));
          request.add(new UpdateDrop(graphUri.toASCIIString()));
  
          // Use create form for Sesame-based engines. TODO: Generalise and push to config.
          UpdateProcessor processor = UpdateExecutionFactory.createRemoteForm(request, this.getSparqlUpdateEndpoint().toASCIIString());
          processor.execute(); // TODO: anyway to know if things went ok?
      }
docs: Delete Graph using SPARQL Update
  
  @param graphUri