1   /*
2    * FunctionalProperty.java
3    *
4    * Copyright (c) 2002-2004, The University of Sheffield.
5    *
6    * This file is part of GATE (see http://gate.ac.uk/), and is free
7    * software, licenced under the GNU Library General Public License,
8    * Version 2, June1991.
9    *
10   * A copy of this licence is included in the distribution in the file
11   * licence.html, and is also available at http://gate.ac.uk/gate/licence.html.
12   *
13   * Kalina Bontcheva 11/2003
14   *
15   *
16   *  $Id: FunctionalProperty.java,v 1.1 2004/07/23 17:48:08 kalina Exp $
17   */
18  
19  package gate.creole.ontology;
20  
21  
22  /**
23   * A property, P, is tagged as functional if it
24  satisfies the following axiom: P(x, y) and P(x, z) -> y = z.
25   * The range of a functional property can be both
26   * an object (as in DatatypeProperty) and KBClass
27   * (as in ObjectProperty).
28   */
29  public interface FunctionalProperty extends Property {
30    public Object getRange();
31  }