1 /*
2 wsmo4j - a WSMO API and Reference Implementation
3 Copyright (c) 2005 University of Innsbruck, Austria
4 2005 National University of Ireland, Galway
5 This library is free software; you can redistribute it and/or modify it under
6 the terms of the GNU Lesser General Public License as published by the Free
7 Software Foundation; either version 2.1 of the License, or (at your option)
8 any later version.
9 This library is distributed in the hope that it will be useful, but WITHOUT
10 ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
11 FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more
12 details.
13 You should have received a copy of the GNU Lesser General Public License along
14 with this library; if not, write to the Free Software Foundation, Inc.,
15 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
16 */
17
18 package org.deri.wsmo4j.logicalexpression;
19
20
21 import org.omwg.logicalexpression.*;
22
23
24 /**
25 * @author DERI Innsbruck, reto.krummenacher@deri.org
26 * @author DERI Innsbruck, thomas.haselwanter@deri.org
27 */
28 public class NegationAsFailureImpl
29 extends UnaryImpl
30 implements NegationAsFailure {
31
32 public NegationAsFailureImpl(LogicalExpression expr)
33 throws IllegalArgumentException {
34 super(expr);
35 }
36
37 public void accept(Visitor v) {
38 v.visitNegationAsFailure(this);
39 }
40
41 /**
42 * <p>
43 * The <code>equals</code> method implements an equivalence relation
44 * on non-null object references. Unary expressions are equal if their operator
45 * and their logical expression are equal.
46 * </p>
47 * <p>
48 * It is generally necessary to override the <code>hashCode</code> method whenever this method
49 * is overridden.
50 * </p>
51 * @param o the reference object with which to compare.
52 * @return <code>true</code> if this object is the same as the obj
53 * argument; <code>false</code> otherwise.
54 * @see java.lang.Object#equals(java.lang.Object)
55 * @see java.lang.Object#hashCode()
56 */
57 public boolean equals(Object o) {
58 if (o instanceof NegationAsFailure) {
59 NegationAsFailure u = (NegationAsFailure)o;
60 return expr.equals(u.getOperand());
61 }
62 return false;
63 }
64
65 }