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1   /*
2    * SAT4J: a SATisfiability library for Java Copyright (C) 2004-2006 Daniel Le Berre
3    * 
4    * Based on the original minisat specification from:
5    * 
6    * An extensible SAT solver. Niklas E?n and Niklas S?rensson. Proceedings of the
7    * Sixth International Conference on Theory and Applications of Satisfiability
8    * Testing, LNCS 2919, pp 502-518, 2003.
9    * 
10   * This library is free software; you can redistribute it and/or modify it under
11   * the terms of the GNU Lesser General Public License as published by the Free
12   * Software Foundation; either version 2.1 of the License, or (at your option)
13   * any later version.
14   * 
15   * This library is distributed in the hope that it will be useful, but WITHOUT
16   * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
17   * FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more
18   * details.
19   * 
20   * You should have received a copy of the GNU Lesser General Public License
21   * along with this library; if not, write to the Free Software Foundation, Inc.,
22   * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
23   * 
24   */
25  package org.sat4j.minisat.constraints.cnf;
26  
27  import org.sat4j.minisat.core.ILits;
28  import org.sat4j.minisat.core.UnitPropagationListener;
29  import org.sat4j.specs.IVecInt;
30  
31  public class OriginalWLClause extends WLClause {
32  
33      public OriginalWLClause(IVecInt ps, ILits voc) {
34          super(ps, voc);
35      }
36  
37      /**
38       * 
39       */
40      private static final long serialVersionUID = 1L;
41  
42      /*
43       * (non-Javadoc)
44       * 
45       * @see org.sat4j.minisat.constraints.cnf.WLClause#register()
46       */
47      public void register() {
48          assert lits.length > 1;
49          voc.watch(lits[0] ^ 1, this);
50          voc.watch(lits[1] ^ 1, this);
51      }
52  
53      public boolean learnt() {
54          return false;
55      }
56  
57      public void setLearnt() {
58          // do nothing
59      }
60  
61      /**
62       * Creates a brand new clause, presumably from external data.
63       * 
64       * @param s
65       *            the object responsible for unit propagation
66       * @param voc
67       *            the vocabulary
68       * @param literals
69       *            the literals to store in the clause
70       * @return the created clause or null if the clause should be ignored
71       *         (tautology for example)
72       */
73      public static OriginalWLClause brandNewClause(UnitPropagationListener s,
74              ILits voc, IVecInt literals) {
75          OriginalWLClause c = new OriginalWLClause(literals, voc);
76          c.register();
77          return c;
78      }
79  }