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 pseudo boolean algorithms described in:
20 * A fast pseudo-Boolean constraint solver Chai, D.; Kuehlmann, A.
21 * Computer-Aided Design of Integrated Circuits and Systems, IEEE Transactions on
22 * Volume 24, Issue 3, March 2005 Page(s): 305 - 317
23 *
24 * and
25 * Heidi E. Dixon, 2004. Automating Pseudo-Boolean Inference within a DPLL
26 * Framework. Ph.D. Dissertation, University of Oregon.
27 *******************************************************************************/
28 package org.sat4j.pb.reader;
29
30 import java.io.IOException;
31
32 import org.sat4j.core.VecInt;
33 import org.sat4j.pb.IPBSolver;
34 import org.sat4j.reader.ParseFormatException;
35 import org.sat4j.specs.IVecInt;
36
37 /**
38 * @author anne
39 *
40 */
41 public class OPBEclipseReader2007 extends OPBReader2007 {
42
43 /**
44 *
45 */
46 private static final long serialVersionUID = 1L;
47
48 private final IVecInt varExplain = new VecInt();
49
50 /**
51 * @param solver
52 */
53 public OPBEclipseReader2007(IPBSolver solver) {
54 super(solver);
55 }
56
57 /**
58 * callback called before we read the list for variables explanation
59 */
60 protected void beginListOfVariables() {
61 }
62
63 /**
64 * callback called after we've read the list for variable explanation
65 */
66 protected void endListOfVariables() {
67 }
68
69 /**
70 * read the list for variables explanation (if any) calls
71 * beginListOfVariables and endListOfVariables
72 *
73 * @throws IOException
74 * @throws ParseException
75 */
76 @Override
77 protected void readVariablesExplanation() throws IOException,
78 ParseFormatException {
79 char c;
80 StringBuffer var = new StringBuffer();
81
82 // read variables line (if any)
83 // if the problem is unsatisfiable, and if these variables are part of
84 // the reason of the conflict
85 // then an explanation should be produced for these variables
86
87 skipSpaces();
88 c = get();
89 if (c != 'e') {
90 // no variables line
91 putback(c);
92 return;
93 }
94
95 hasVariablesExplanation = true;
96 if (get() == 'x' && get() == 'p' && get() == 'l' && get() == 'a'
97 && get() == 'i' && get() == 'n' && get() == ':') {
98 beginListOfVariables(); // callback
99
100 while (!eof()) {
101 readIdentifier(var);
102 varExplain.push(translateVarToId(var.toString()));
103
104 skipSpaces();
105 c = get();
106 if (c == ';')
107 break; // end of list of variables
108 putback(c);
109 }
110
111 endListOfVariables();
112 } else
113 throw new ParseFormatException(
114 "input format error: 'explain:' expected");
115
116 }
117
118 @Override
119 public IVecInt getListOfVariables() {
120 if (hasVariablesExplanation) {
121 IVecInt tmp = new VecInt();
122 varExplain.moveTo(tmp);
123 return tmp;
124 }
125 return null;
126 }
127
128 }