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.UnitPropagationListener;
33
34 /**
35 * This interface is to be implemented by the classes wanted to be notified of
36 * the falsification of a literal.
37 *
38 * @author leberre
39 */
40 public interface Propagatable {
41
42 /**
43 * Propagate the truth value of a literal in constraints in which that
44 * literal is falsified.
45 *
46 * @param s
47 * something able to perform unit propagation
48 * @param p
49 * the literal being propagated. Its negation must appear in the
50 * constraint.
51 * @return false iff an inconsistency (a contradiction) is detected.
52 */
53 boolean propagate(UnitPropagationListener s, int p);
54
55 /**
56 * Allow to access a constraint view of the propagatable to avoid casting.
57 * In most cases, the constraint will implement directly propagatable thus
58 * will return itself. It will also also the implementation of more
59 * sophisticated watching strategy.
60 *
61 * @return the constraint associated to that propagatable.
62 * @since 2.3.2
63 */
64 Constr toConstraint();
65 }