1 /*******************************************************************************
2 * SAT4J: a SATisfiability library for Java Copyright (C) 2004-2008 Daniel Le Berre
3 *
4 * All rights reserved. This program and the accompanying materials
5 * are made available under the terms of the Eclipse Public License v1.0
6 * which accompanies this distribution, and is available at
7 * http://www.eclipse.org/legal/epl-v10.html
8 *
9 * Alternatively, the contents of this file may be used under the terms of
10 * either the GNU Lesser General Public License Version 2.1 or later (the
11 * "LGPL"), in which case the provisions of the LGPL are applicable instead
12 * of those above. If you wish to allow use of your version of this file only
13 * under the terms of the LGPL, and not to allow others to use your version of
14 * this file under the terms of the EPL, indicate your decision by deleting
15 * the provisions above and replace them with the notice and other provisions
16 * required by the LGPL. If you do not delete the provisions above, a recipient
17 * may use your version of this file under the terms of the EPL or the LGPL.
18 *
19 * Based on the original MiniSat specification from:
20 *
21 * An extensible SAT solver. Niklas Een and Niklas Sorensson. Proceedings of the
22 * Sixth International Conference on Theory and Applications of Satisfiability
23 * Testing, LNCS 2919, pp 502-518, 2003.
24 *
25 * See www.minisat.se for the original solver in C++.
26 *
27 *******************************************************************************/
28 package org.sat4j.minisat.constraints.cnf;
29
30 import static org.sat4j.core.LiteralsUtils.neg;
31 import org.sat4j.minisat.core.ILits;
32 import org.sat4j.minisat.core.UnitPropagationListener;
33 import org.sat4j.specs.IVecInt;
34
35 public class OriginalHTClause extends HTClause {
36
37 public OriginalHTClause(IVecInt ps, ILits voc) {
38 super(ps, voc);
39 }
40
41 /**
42 *
43 */
44 private static final long serialVersionUID = 1L;
45
46 /*
47 * (non-Javadoc)
48 *
49 * @see org.sat4j.minisat.constraints.cnf.WLClause#register()
50 */
51 public void register() {
52 voc.attach(neg(head), this);
53 voc.attach(neg(tail), this);
54 }
55
56 public boolean learnt() {
57 return false;
58 }
59
60 public void setLearnt() {
61 // do nothing
62 }
63
64 /**
65 * Creates a brand new clause, presumably from external data.
66 *
67 * @param s
68 * the object responsible for unit propagation
69 * @param voc
70 * the vocabulary
71 * @param literals
72 * the literals to store in the clause
73 * @return the created clause or null if the clause should be ignored
74 * (tautology for example)
75 */
76 public static OriginalHTClause brandNewClause(UnitPropagationListener s,
77 ILits voc, IVecInt literals) {
78 OriginalHTClause c = new OriginalHTClause(literals, voc);
79 c.register();
80 return c;
81 }
82 }