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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.tools;
31  
32  import java.math.BigInteger;
33  import java.util.ArrayList;
34  import java.util.List;
35  
36  import org.sat4j.core.Vec;
37  import org.sat4j.pb.IPBSolver;
38  import org.sat4j.pb.ObjectiveFunction;
39  import org.sat4j.specs.ContradictionException;
40  import org.sat4j.specs.IConstr;
41  import org.sat4j.specs.IVec;
42  import org.sat4j.specs.IVecInt;
43  import org.sat4j.specs.TimeoutException;
44  import org.sat4j.tools.LexicoDecorator;
45  
46  public class LexicoDecoratorPB extends LexicoDecorator<IPBSolver> implements
47          IPBSolver {
48  
49      /**
50  	 * 
51  	 */
52      private static final long serialVersionUID = 1L;
53  
54      private final List<ObjectiveFunction> objs = new ArrayList<ObjectiveFunction>();
55      private BigInteger bigCurrentValue;
56  
57      public LexicoDecoratorPB(IPBSolver solver) {
58          super(solver);
59      }
60  
61      public IConstr addPseudoBoolean(IVecInt lits, IVec<BigInteger> coeffs,
62              boolean moreThan, BigInteger d) throws ContradictionException {
63          return decorated().addPseudoBoolean(lits, coeffs, moreThan, d);
64      }
65  
66      public void setObjectiveFunction(ObjectiveFunction obj) {
67          throw new UnsupportedOperationException();
68  
69      }
70  
71      public ObjectiveFunction getObjectiveFunction() {
72          throw new UnsupportedOperationException();
73      }
74  
75      @Override
76      public boolean admitABetterSolution(IVecInt assumps)
77              throws TimeoutException {
78          decorated().setObjectiveFunction(this.objs.get(this.currentCriterion));
79          return super.admitABetterSolution(assumps);
80      }
81  
82      @Override
83      public void addCriterion(IVecInt literals) {
84          this.objs.add(new ObjectiveFunction(literals, new Vec<BigInteger>(
85                  literals.size(), BigInteger.ONE)));
86      }
87  
88      public void addCriterion(IVecInt literals, IVec<BigInteger> coefs) {
89          this.objs.add(new ObjectiveFunction(literals, coefs));
90      }
91  
92      @Override
93      protected Number evaluate() {
94          this.bigCurrentValue = this.objs.get(this.currentCriterion)
95                  .calculateDegree(this);
96          return this.bigCurrentValue;
97      }
98  
99      @Override
100     protected void fixCriterionValue() throws ContradictionException {
101         addPseudoBoolean(this.objs.get(this.currentCriterion).getVars(),
102                 this.objs.get(this.currentCriterion).getCoeffs(), true,
103                 this.bigCurrentValue);
104         addPseudoBoolean(this.objs.get(this.currentCriterion).getVars(),
105                 this.objs.get(this.currentCriterion).getCoeffs(), false,
106                 this.bigCurrentValue);
107     }
108 
109     @Override
110     protected IConstr discardSolutionsForOptimizing()
111             throws ContradictionException {
112         return addPseudoBoolean(this.objs.get(this.currentCriterion).getVars(),
113                 this.objs.get(this.currentCriterion).getCoeffs(), false,
114                 this.bigCurrentValue.subtract(BigInteger.ONE));
115     }
116 
117     @Override
118     protected int numberOfCriteria() {
119         return this.objs.size();
120     }
121 
122     public IConstr addAtMost(IVecInt literals, IVecInt coeffs, int degree)
123             throws ContradictionException {
124         throw new UnsupportedOperationException();
125     }
126 
127     public IConstr addAtMost(IVecInt literals, IVec<BigInteger> coeffs,
128             BigInteger degree) throws ContradictionException {
129         throw new UnsupportedOperationException();
130     }
131 
132     public IConstr addAtLeast(IVecInt literals, IVecInt coeffs, int degree)
133             throws ContradictionException {
134         throw new UnsupportedOperationException();
135     }
136 
137     public IConstr addAtLeast(IVecInt literals, IVec<BigInteger> coeffs,
138             BigInteger degree) throws ContradictionException {
139         throw new UnsupportedOperationException();
140     }
141 
142     public IConstr addExactly(IVecInt literals, IVecInt coeffs, int weight)
143             throws ContradictionException {
144         throw new UnsupportedOperationException();
145     }
146 
147     public IConstr addExactly(IVecInt literals, IVec<BigInteger> coeffs,
148             BigInteger weight) throws ContradictionException {
149         throw new UnsupportedOperationException();
150     }
151 
152 }