1 /*
2 wsmo4j - a WSMO API and Reference Implementation
3 Copyright (c) 2005, University of Innsbruck, Austria
4 This library is free software; you can redistribute it and/or modify it under
5 the terms of the GNU Lesser General Public License as published by the Free
6 Software Foundation; either version 2.1 of the License, or (at your option)
7 any later version.
8 This library is distributed in the hope that it will be useful, but WITHOUT
9 ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
10 FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more
11 details.
12 You should have received a copy of the GNU Lesser General Public License along
13 with this library; if not, write to the Free Software Foundation, Inc.,
14 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
15 */
16 package org.deri.wsmo4j.logicalexpression.util;
17
18 import java.util.Vector;
19
20 import org.deri.wsmo4j.validator.WsmlDLValidator;
21 import org.omwg.logicalexpression.LogicalExpression;
22 import org.omwg.ontology.Variable;
23 import org.wsmo.factory.Factory;
24 import org.wsmo.validator.ValidationError;
25 import org.wsmo.validator.ValidationWarning;
26
27 /**
28 * Utility class to extract the root/s variable/s from a WSML-DL
29 * logical expression.
30 *
31 * <pre>
32 * Created on Sep 27, 2006
33 * Committed by $Author: morcen $
34 * $Source$,
35 * </pre>
36 *
37 * @author Nathalie Steinmetz, DERI Innsbruck
38 * @version $Revision: 1946 $ $Date: 2007-04-02 15:13:28 +0300 (Mon, 02 Apr 2007) $
39 */
40 public class GetRootUtil {
41
42 public GetRootUtil() {
43
44 }
45
46 /**
47 * Validates a given formula and gets the root variable if it is a valid
48 * WSML-DL formula.
49 *
50 * @param logExpr
51 * @return root Variable or null, if there is no root variable or if the
52 * formula is not valid WSML-DL
53 */
54 public Variable getRootVariable(LogicalExpression logExpr) {
55 WsmlDLValidator validator = new WsmlDLValidator(
56 Factory.createLogicalExpressionFactory(null));
57 boolean valid = validator.isValid(logExpr, new Vector <ValidationError>(), new Vector <ValidationWarning>());
58 if (valid) {
59 return validator.getRootVariable(logExpr);
60 }
61 else {
62 return null;
63 }
64 }
65
66 }
67 /*
68 * $Log$
69 * Revision 1.3 2007/04/02 12:13:23 morcen
70 * Generics support added to wsmo-api, wsmo4j and wsmo-test
71 *
72 * Revision 1.2 2006/09/28 14:45:10 nathaliest
73 * *** empty log message ***
74 *
75 * Revision 1.1 2006/09/28 13:11:34 nathaliest
76 * added utility method to geet root variable of valid WSML-DL formula and added corresponding tests
77 *
78 *
79 */