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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.pb.reader;
31  
32  import java.io.IOException;
33  
34  import org.sat4j.core.VecInt;
35  import org.sat4j.pb.IPBSolver;
36  import org.sat4j.reader.ParseFormatException;
37  import org.sat4j.specs.IVecInt;
38  
39  /**
40   * @author anne
41   * 
42   */
43  public class OPBEclipseReader2007 extends OPBReader2007 {
44  
45      /**
46  	 * 
47  	 */
48      private static final long serialVersionUID = 1L;
49  
50      private final IVecInt varExplain = new VecInt();
51  
52      /**
53       * @param solver
54       */
55      public OPBEclipseReader2007(IPBSolver solver) {
56          super(solver);
57      }
58  
59      /**
60       * callback called before we read the list for variables explanation
61       */
62      protected void beginListOfVariables() {
63      }
64  
65      /**
66       * callback called after we've read the list for variable explanation
67       */
68      protected void endListOfVariables() {
69      }
70  
71      /**
72       * read the list for variables explanation (if any) calls
73       * beginListOfVariables and endListOfVariables
74       * 
75       * @throws IOException
76       * @throws ParseException
77       */
78      @Override
79      protected void readVariablesExplanation() throws IOException,
80              ParseFormatException {
81          char c;
82          StringBuffer var = new StringBuffer();
83  
84          // read variables line (if any)
85          // if the problem is unsatisfiable, and if these variables are part of
86          // the reason of the conflict
87          // then an explanation should be produced for these variables
88  
89          skipSpaces();
90          c = get();
91          if (c != 'e') {
92              // no variables line
93              putback(c);
94              return;
95          }
96  
97          this.hasVariablesExplanation = true;
98          if (get() == 'x' && get() == 'p' && get() == 'l' && get() == 'a'
99                  && get() == 'i' && get() == 'n' && get() == ':') {
100             beginListOfVariables(); // callback
101 
102             while (!eof()) {
103                 readIdentifier(var);
104                 this.varExplain.push(translateVarToId(var.toString()));
105 
106                 skipSpaces();
107                 c = get();
108                 if (c == ';') {
109                     break; // end of list of variables
110                 }
111                 putback(c);
112             }
113 
114             endListOfVariables();
115         } else {
116             throw new ParseFormatException(
117                     "input format error: 'explain:' expected");
118         }
119 
120     }
121 
122     @Override
123     public IVecInt getListOfVariables() {
124         if (this.hasVariablesExplanation) {
125             IVecInt tmp = new VecInt();
126             this.varExplain.moveTo(tmp);
127             return tmp;
128         }
129         return null;
130     }
131 
132 }