code: package it.unibz.inf.ontop.rdf4j.query;
  
  import com.google.common.collect.ImmutableList;
  import com.google.common.collect.ImmutableSet;
  import org.apache.commons.rdf.api.IRI;
  import org.eclipse.rdf4j.query.GraphQuery;
  
  /**
   * GraphQuery with additional information about the materialization
   */
  public interface MaterializationGraphQuery extends GraphQuery {
      /**
       * Number of RDF triples that have been materialized.
       *
       * Increases until the materialization completes.
       */
      long getTripleCountSoFar();
  
      /**
       * Returns true if a problem has occurred so far.
       *
       * May evolve until the materialization completes.
       *
       */
      boolean hasEncounteredProblemsSoFar();
  
      /**
       * RDF properties/classes for which, so far, a problem occurred during the materialization of their triples.
       *
       * May evolve until the materialization completes.
       *
       */
      ImmutableList<IRI> getPossiblyIncompleteRDFPropertiesAndClassesSoFar();
  
      /**
       * RDF predicates/classes that are considered for materialization.
       *
       *
       */
      ImmutableSet<IRI> getSelectedVocabulary();
  }
  