1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
|
package org.onap.ccsdk.sli.core.slipluginutils.slitopologyutils.graph;
import com.google.common.collect.ImmutableSet;
import com.google.common.collect.ImmutableSetMultimap;
import java.util.Objects;
import java.util.Set;
import static com.google.common.base.MoreObjects.toStringHelper;
import static com.google.common.base.Preconditions.checkNotNull;
/**
* Immutable directionless graph implementation using adjacency lists.
* @param <V>
* @param <E>
*/
public class Graph<V extends Vertex, E extends Edge<V>>
{
private final Set<V> vertexes;
private final Set<E> edges;
private final ImmutableSetMultimap<V, E> sources;
private final ImmutableSetMultimap<V, E> destinations;
/**
* Creates a graph comprising of the specified vertexes and edges.
*
* @param vertexes set of graph vertexes
* @param edges set of graph edges
*/
public Graph(Set<V> vertexes, Set<E> edges) {
checkNotNull(vertexes, "Vertex set cannot be null");
checkNotNull(edges, "Edge set cannot be null");
// Record ingress/egress edges for each vertex.
ImmutableSetMultimap.Builder<V, E> srcMap = ImmutableSetMultimap.builder();
ImmutableSetMultimap.Builder<V, E> dstMap = ImmutableSetMultimap.builder();
// Also make sure that all edge end-points are added as vertexes
ImmutableSet.Builder<V> actualVertexes = ImmutableSet.builder();
actualVertexes.addAll(vertexes);
for (E edge : edges) {
srcMap.put(edge.src(), edge);
actualVertexes.add(edge.src());
dstMap.put(edge.dst(), edge);
actualVertexes.add(edge.dst());
}
// Make an immutable copy of the edge and vertex sets
this.edges = ImmutableSet.copyOf(edges);
this.vertexes = actualVertexes.build();
// Build immutable copies of sources and destinations edge maps
sources = srcMap.build();
destinations = dstMap.build();
}
public Set<V> getVertexes() {
return vertexes;
}
public Set<E> getEdges() {
return edges;
}
public Set<E> getEdgesFrom(V src) {
return sources.get(src);
}
public Set<E> getEdgesTo(V dst) {
return destinations.get(dst);
}
@Override
public boolean equals(Object obj) {
if (this == obj) {
return true;
}
if (obj instanceof Graph) {
Graph that = (Graph) obj;
return this.getClass() == that.getClass() &&
Objects.equals(this.vertexes, that.vertexes) &&
Objects.equals(this.edges, that.edges);
}
return false;
}
@Override
public int hashCode() {
return Objects.hash(vertexes, edges);
}
@Override
public String toString() {
return toStringHelper(this)
.add("vertexes", vertexes)
.add("edges", edges)
.toString();
}
}
|