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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  
20  package org.sat4j.pb.tools;
21  
22  import org.sat4j.core.Vec;
23  import org.sat4j.specs.ContradictionException;
24  import org.sat4j.specs.IConstr;
25  import org.sat4j.specs.IVec;
26  import org.sat4j.specs.IVecInt;
27  
28  /**
29   * That class represents the RHS of an implication.
30   * 
31   * @author daniel
32   * 
33   * @param <T>
34   * @param <C>
35   */
36  public class ImplicationRHS<T, C> {
37  
38  	private final IVecInt clause;
39  	private final DependencyHelper<T, C> helper;
40  
41  	private final IVec<IConstr> toName = new Vec<IConstr>();
42  
43  	public ImplicationRHS(DependencyHelper<T, C> helper, IVecInt clause) {
44  		this.clause = clause;
45  		this.helper = helper;
46  	}
47  
48  	/**
49  	 * Build an implication with a conjunction of literals in the RHS.
50  	 * 
51  	 * @param thing
52  	 *            a domain object that will appear positively.
53  	 * @return a RHS conjunction of literals.
54  	 * @throws ContradictionException
55  	 */
56  	public ImplicationAnd<T, C> implies(T thing) throws ContradictionException {
57  		ImplicationAnd<T, C> and = new ImplicationAnd<T, C>(helper, clause);
58  		and.and(thing);
59  		return and;
60  	}
61  
62  	/**
63  	 * Build an implication with a disjunction of literals in the RHS.
64  	 * 
65  	 * @param thing
66  	 *            a domain object
67  	 * @return an object used to name the constraint. The constraint MUST BE
68  	 *         NAMED.
69  	 * @throws ContradictionException
70  	 */
71  	public ImplicationNamer<T, C> implies(T... things)
72  			throws ContradictionException {
73  		for (T t : things) {
74  			clause.push(helper.getIntValue(t));
75  		}
76  		toName.push(helper.solver.addClause(clause));
77  		return new ImplicationNamer<T, C>(helper, toName);
78  	}
79  
80  	/**
81  	 * Build an implication with a conjunction of literals in the RHS.
82  	 * 
83  	 * @param thing
84  	 *            a domain object that will appear negatively.
85  	 * @return a RHS conjunction of literals.
86  	 * @throws ContradictionException
87  	 */
88  	public ImplicationAnd<T, C> impliesNot(T thing)
89  			throws ContradictionException {
90  		ImplicationAnd<T, C> and = new ImplicationAnd<T, C>(helper, clause);
91  		and.andNot(thing);
92  		return and;
93  	}
94  
95  }