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1   /*******************************************************************************
2    * SAT4J: a SATisfiability library for Java Copyright (C) 2004, 2012 Artois University and CNRS
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   * Contributors:
28   *   CRIL - initial API and implementation
29   *******************************************************************************/
30  package org.sat4j.minisat.core;
31  
32  import org.sat4j.specs.ContradictionException;
33  import org.sat4j.specs.IVec;
34  import org.sat4j.specs.IVecInt;
35  
36  /**
37   * The aim of the factory is to provide a concrete implementation of clauses,
38   * cardinality constraints and pseudo boolean consraints.
39   * 
40   * @author leberre
41   */
42  public interface DataStructureFactory {
43  
44      /**
45       * @param literals
46       *            a set of literals using Dimacs format (signed non null
47       *            integers).
48       * @return null if the constraint is a tautology.
49       * @throws ContradictionException
50       *             the constraint is trivially unsatisfiable.
51       * @throws UnsupportedOperationException
52       *             there is no concrete implementation for that constraint.
53       */
54      Constr createClause(IVecInt literals) throws ContradictionException;
55  
56      Constr createUnregisteredClause(IVecInt literals);
57  
58      void learnConstraint(Constr constr);
59  
60      /**
61       * Create a cardinality constraint of the form sum li >= degree.
62       * 
63       * @param literals
64       *            a set of literals.
65       * @param degree
66       *            the degree of the cardinality constraint.
67       * @return a constraint stating that at least degree literals are satisfied.
68       * @throws ContradictionException
69       */
70      Constr createCardinalityConstraint(IVecInt literals, int degree)
71              throws ContradictionException;
72  
73      void setUnitPropagationListener(UnitPropagationListener s);
74  
75      void setLearner(Learner l);
76  
77      void reset();
78  
79      ILits getVocabulary();
80  
81      /**
82       * @param p
83       * @return a vector containing all the objects to be notified of the
84       *         satisfaction of that literal.
85       */
86      IVec<Propagatable> getWatchesFor(int p);
87  
88      /**
89       * @param p
90       * @param i
91       *            the index of the conflicting constraint
92       */
93      void conflictDetectedInWatchesFor(int p, int i);
94  }