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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  
31  package org.sat4j.pb.tools;
32  
33  import java.math.BigInteger;
34  
35  public class WeightedObject<T> implements Comparable<WeightedObject<T>> {
36  
37      public final T thing;
38      private BigInteger weight;
39  
40      private WeightedObject(T thing, BigInteger weight) {
41          this.thing = thing;
42          this.weight = weight;
43      }
44  
45      public BigInteger getWeight() {
46          return this.weight;
47      }
48  
49      public void increaseWeight(BigInteger delta) {
50          this.weight = this.weight.add(delta);
51      }
52  
53      public int compareTo(WeightedObject<T> arg0) {
54          return this.weight.compareTo(arg0.getWeight());
55      }
56  
57      public static <E> WeightedObject<E> newWO(E e, int w) {
58          return new WeightedObject<E>(e, BigInteger.valueOf(w));
59      }
60  
61      public static <E> WeightedObject<E> newWO(E e, long w) {
62          return new WeightedObject<E>(e, BigInteger.valueOf(w));
63      }
64  
65      public static <E> WeightedObject<E> newWO(E e, BigInteger w) {
66          return new WeightedObject<E>(e, w);
67      }
68  
69      @Override
70      public int hashCode() {
71          final int prime = 31;
72          int result = 1;
73          result = prime * result
74                  + (this.thing == null ? 0 : this.thing.hashCode());
75          result = prime * result
76                  + (this.weight == null ? 0 : this.weight.hashCode());
77          return result;
78      }
79  
80      @Override
81      public boolean equals(Object obj) {
82          if (this == obj) {
83              return true;
84          }
85          if (obj == null) {
86              return false;
87          }
88          if (getClass() != obj.getClass()) {
89              return false;
90          }
91          WeightedObject<?> other = (WeightedObject<?>) obj;
92          if (this.thing == null) {
93              if (other.thing != null) {
94                  return false;
95              }
96          } else if (!this.thing.equals(other.thing)) {
97              return false;
98          }
99          if (this.weight == null) {
100             if (other.weight != null) {
101                 return false;
102             }
103         } else if (!this.weight.equals(other.weight)) {
104             return false;
105         }
106         return true;
107     }
108 }