1 salcianu 1.1.2.1 // PAEdge.java, created Wed Feb 16 15:02:44 2000 by salcianu
2 cananian 1.1.2.10 // Copyright (C) 2000 Alexandru SALCIANU <salcianu@retezat.lcs.mit.edu>
3 salcianu 1.1.2.1 // Licensed under the terms of the GNU GPL; see COPYING for details.
4 salcianu 1.1.2.1 package harpoon.Analysis.PointerAnalysis;
5 salcianu 1.1.2.1
6 salcianu 1.1.2.2 import java.util.Set;
7 salcianu 1.1.2.7 import java.util.Map;
8 salcianu 1.1.2.6 import java.util.HashSet;
9 salcianu 1.1.2.6 import java.util.Iterator;
10 salcianu 1.1.2.2
11 salcianu 1.1.2.8 import harpoon.Util.DataStructs.Relation;
12 salcianu 1.1.2.8 import harpoon.Util.DataStructs.LightRelation;
13 salcianu 1.1.2.8
14 salcianu 1.1.2.1 /**
15 salcianu 1.1.2.1 * <code>PAEdge</code>
16 salcianu 1.1.2.1 *
17 cananian 1.1.2.10 * @author Alexandru SALCIANU <salcianu@retezat.lcs.mit.edu>
18 cananian 1.3 * @version $Id: PAEdge.java,v 1.3 2004/02/08 03:20:03 cananian Exp $
19 salcianu 1.1.2.1 */
20 salcianu 1.1.2.9 public class PAEdge implements java.io.Serializable {
21 salcianu 1.1.2.1
22 salcianu 1.1.2.1 PANode n1;
23 salcianu 1.1.2.1 String f;
24 salcianu 1.1.2.1 PANode n2;
25 salcianu 1.1.2.1
26 salcianu 1.1.2.1 /** Creates a <code>PAEdge</code>. */
27 salcianu 1.1.2.1 public PAEdge(PANode n1, String f, PANode n2) {
28 salcianu 1.1.2.1 this.n1 = n1;
29 salcianu 1.1.2.1 this.f = f;
30 salcianu 1.1.2.1 this.n2 = n2;
31 salcianu 1.1.2.6 }
32 salcianu 1.1.2.6
33 salcianu 1.1.2.7 /* Project this edge through the relation <code>mu</code>. */
34 salcianu 1.1.2.6 public Set project(Relation mu){
35 salcianu 1.1.2.6 Set edges = new HashSet();
36 cananian 1.3 for(Object new_n1O : mu.getValues(n1)) {
37 cananian 1.3 PANode new_n1 = (PANode) new_n1O;
38 cananian 1.3 for(Object new_n2O : mu.getValues(n2)) {
39 cananian 1.3 PANode new_n2 = (PANode) new_n2O;
40 salcianu 1.1.2.6 edges.add(new PAEdge(new_n1, f, new_n2));
41 salcianu 1.1.2.6 }
42 salcianu 1.1.2.6 }
43 salcianu 1.1.2.6 return edges;
44 salcianu 1.1.2.7 }
45 salcianu 1.1.2.7
46 salcianu 1.1.2.7 /* Specialize <code>this</code> edge by using the mapping
47 salcianu 1.1.2.7 <code>map</code>. <code>map</code> should be a mappig from
48 salcianu 1.1.2.7 <code>PANode</code> to <code>PANode</code>.
49 salcianu 1.1.2.7 Returns an edge obtained from <code>this</code>
50 salcianu 1.1.2.7 one by translating the two ends of it according to the mapping
51 salcianu 1.1.2.7 <code>map</code>. Each node that don't appear in <code>map</code>
52 salcianu 1.1.2.7 is implicitly assumed to be mapped to itself.
53 salcianu 1.1.2.7 This method is smart enough not to reallocated a new object if
54 salcianu 1.1.2.7 none of its ends is mapped to something else; in this case, it returns
55 salcianu 1.1.2.7 <code>this</code> object. */
56 salcianu 1.1.2.7 public PAEdge specialize(Map map){
57 salcianu 1.1.2.7 PANode n1p = (PANode) map.get(n1);
58 salcianu 1.1.2.7 PANode n2p = (PANode) map.get(n2);
59 salcianu 1.1.2.7 if(n1p == null){
60 salcianu 1.1.2.7 // hack to avoid regenerating the same edge
61 salcianu 1.1.2.7 if(n2p == null) return this;
62 salcianu 1.1.2.7 // an unmaped nodes is implicitly maped to itself
63 salcianu 1.1.2.7 n1p = n1;
64 salcianu 1.1.2.7 }
65 salcianu 1.1.2.7 // an unmaped nodes is implicitly maped to itself
66 salcianu 1.1.2.7 if(n2p == null) n2p = n2;
67 salcianu 1.1.2.7 return new PAEdge(n1p,f,n2p);
68 salcianu 1.1.2.1 }
69 salcianu 1.1.2.1
70 salcianu 1.1.2.1 /** Checks the equality of two edges. */
71 salcianu 1.1.2.1 public boolean equals(Object o){
72 salcianu 1.1.2.1 PAEdge edge2 = (PAEdge) o;
73 salcianu 1.1.2.1 return (n1==edge2.n1) && (n2==edge2.n2) && (f.equals(edge2.f));
74 salcianu 1.1.2.1 }
75 salcianu 1.1.2.1
76 salcianu 1.1.2.1 /** Computes the hash code of <code>this</code> object. */
77 salcianu 1.1.2.1 public int hashCode(){
78 salcianu 1.1.2.1 return n1.hashCode();
79 salcianu 1.1.2.1 }
80 salcianu 1.1.2.1
81 salcianu 1.1.2.1 /** String representation for debug purposes. */
82 salcianu 1.1.2.1 public String toString(){
83 salcianu 1.1.2.1 return "<" + n1.toString() + "," + f + "," + n2.toString() + ">";
84 salcianu 1.1.2.2 }
85 salcianu 1.1.2.2
86 salcianu 1.1.2.3 /** Checks whether <code>this</code> edge refers only to remaining nodes.
87 salcianu 1.1.2.3 This is supposed to be used by <code>keepTheEssential</code> methods.
88 salcianu 1.1.2.5 Warning: <code>isGood</code> is NOT the negation of
89 salcianu 1.1.2.5 <code>isBad</code>. */
90 salcianu 1.1.2.5 boolean isGood(Set remaining_nodes){
91 salcianu 1.1.2.3 return remaining_nodes.contains(n1) && remaining_nodes.contains(n2);
92 salcianu 1.1.2.3 }
93 salcianu 1.1.2.3
94 salcianu 1.1.2.2 /** Checks whether <code>this</code> edge refers to at least one
95 salcianu 1.1.2.2 node from the set <code>bad_nodes</code>. This is supposed to
96 salcianu 1.1.2.2 help us to determine which edges must go when we remove some nodes. */
97 salcianu 1.1.2.5 boolean isBad(Set bad_nodes){
98 salcianu 1.1.2.2 return bad_nodes.contains(n1) || bad_nodes.contains(n2);
99 salcianu 1.1.2.1 }
100 salcianu 1.1.2.1 }
101 salcianu 1.1.2.4
102 salcianu 1.1.2.4
103 salcianu 1.1.2.4
104 salcianu 1.1.2.4
105 cananian 1.2