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18 package jr239.co620;
19 import java.util.HashSet;
20 import java.util.Set;
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27 public class Couple<E>
28 extends HashSet<E>
29 implements Set<E>, Cloneable, java.io.Serializable{
30
31 private static final long serialVersionUID = -0xe1224eeL;
32
33 private Couple(){
34
35 }
36
37 public Couple( E e1, E e2) {
38 super(2);
39 if (e1.equals(e2) ){
40 System.err.println("Couples need unique elementes. Provided couple is: (" + e1+","+ e2+")" );
41 }else{
42 if ( ! (super.add( e1) && super.add(e2)) ){
43 System.err.println("Sytem was unable to create couple:(" + e1+","+ e2+")");
44 }
45 }
46 }
47
48 public boolean add(E e){
49 System.err.println("Couple.add( E e..): Only one element ot the couple was provided");
50 return false;
51 }
52
53
54 public void remove(E e){
55 System.err.println("Couple.remove( E e..): Only one element ot the couple was provided");
56 }
57
58 public boolean remove(E e1, E e2){
59 return ( super.remove(e2) && super.remove(e1));
60 }
61
62
63 public boolean add(E e1, E e2){
64
65 return false;
66 }
67
68 }