content: // This file is part of AceWiki.
  // Copyright 2008-2013, AceWiki developers.
  // 
  // AceWiki is free software: you can redistribute it and/or modify it under the terms of the GNU
  // Lesser General Public License as published by the Free Software Foundation, either version 3 of
  // the License, or (at your option) any later version.
  // 
  // AceWiki is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without
  // even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  // Lesser General Public License for more details.
  // 
  // You should have received a copy of the GNU Lesser General Public License along with AceWiki. If
  // not, see http://www.gnu.org/licenses/.
  
  package ch.uzh.ifi.attempto.acewiki.owl;
  
  import org.semanticweb.owlapi.model.OWLClassExpression;
  import org.semanticweb.owlapi.model.OWLNamedIndividual;
  
  import ch.uzh.ifi.attempto.acewiki.core.Question;
  
  /**
   * This class represents questions with OWL representations.
   * 
   * @author Tobias Kuhn
   */
  public interface OWLQuestion extends OWLSentence, Question {
  
  	/**
  	 * Returns the OWL class expression for this question. All individuals that belong to this
  	 * class expression can be considered answers to the question.
  	 * 
  	 * @return The OWL class expression.
  	 */
  	public abstract OWLClassExpression getQuestionOWLClass();
  
  	/**
  	 * Returns the OWL individual for this question. For questions like "What is Switzerland?", the
  	 * respective individual ("Switzerland") is returned. In all other cases, null is returned.
  	 * 
  	 * @return The OWL individual.
  	 */
  	public abstract OWLNamedIndividual getQuestionOWLIndividual();
  
  }
  