Nikhil Cheerla | f7c2e1a | 2015-07-09 12:06:37 -0700 | [diff] [blame^] | 1 | /* |
| 2 | * Copyright 2015 Open Networking Laboratory |
| 3 | * |
| 4 | * Licensed under the Apache License, Version 2.0 (the "License"); |
| 5 | * you may not use this file except in compliance with the License. |
| 6 | * You may obtain a copy of the License at |
| 7 | * |
| 8 | * http://www.apache.org/licenses/LICENSE-2.0 |
| 9 | * |
| 10 | * Unless required by applicable law or agreed to in writing, software |
| 11 | * distributed under the License is distributed on an "AS IS" BASIS, |
| 12 | * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| 13 | * See the License for the specific language governing permissions and |
| 14 | * limitations under the License. |
| 15 | */ |
| 16 | |
| 17 | |
| 18 | package org.onlab.graph; |
| 19 | |
| 20 | import java.util.List; |
| 21 | import java.util.Objects; |
| 22 | import java.util.Set; |
| 23 | |
| 24 | import static com.google.common.collect.ImmutableSet.of; |
| 25 | import static com.google.common.base.MoreObjects.toStringHelper; |
| 26 | |
| 27 | |
| 28 | public class DisjointPathPair<V extends Vertex, E extends Edge<V>> implements Path<V, E> { |
| 29 | public Path<V, E> path1, path2; |
| 30 | boolean usingPath1 = true; |
| 31 | |
| 32 | /** |
| 33 | * Creates a Disjoint Path Pair from two paths. |
| 34 | * |
| 35 | * @param p1 first path |
| 36 | * @param p2 second path |
| 37 | */ |
| 38 | public DisjointPathPair(Path<V, E> p1, Path<V, E> p2) { |
| 39 | path1 = p1; |
| 40 | path2 = p2; |
| 41 | } |
| 42 | |
| 43 | @Override |
| 44 | public V src() { |
| 45 | return path1.src(); |
| 46 | } |
| 47 | |
| 48 | @Override |
| 49 | public V dst() { |
| 50 | return path1.dst(); |
| 51 | } |
| 52 | |
| 53 | @Override |
| 54 | public double cost() { |
| 55 | if (!hasBackup()) { |
| 56 | return path1.cost(); |
| 57 | } |
| 58 | return path1.cost() + path2.cost(); |
| 59 | } |
| 60 | |
| 61 | @Override |
| 62 | public List<E> edges() { |
| 63 | if (usingPath1 || !hasBackup()) { |
| 64 | return path1.edges(); |
| 65 | } else { |
| 66 | return path2.edges(); |
| 67 | } |
| 68 | } |
| 69 | |
| 70 | /** |
| 71 | * Checks if this path pair contains a backup/secondary path. |
| 72 | * |
| 73 | * @return boolean representing whether it has backup |
| 74 | */ |
| 75 | public boolean hasBackup() { |
| 76 | return path2 != null && path2.edges() != null; |
| 77 | } |
| 78 | |
| 79 | @Override |
| 80 | public String toString() { |
| 81 | return toStringHelper(this) |
| 82 | .add("src", src()) |
| 83 | .add("dst", dst()) |
| 84 | .add("cost", cost()) |
| 85 | .add("edges", edges()) |
| 86 | .toString(); |
| 87 | } |
| 88 | |
| 89 | @Override |
| 90 | public int hashCode() { |
| 91 | Set<Path<V, E>> paths; |
| 92 | if (!hasBackup()) { |
| 93 | paths = of(path1); |
| 94 | } else { |
| 95 | paths = of(path1, path2); |
| 96 | } |
| 97 | return Objects.hash(paths); |
| 98 | } |
| 99 | |
| 100 | @Override |
| 101 | public boolean equals(Object obj) { |
| 102 | if (this == obj) { |
| 103 | return true; |
| 104 | } |
| 105 | if (obj instanceof DisjointPathPair) { |
| 106 | final DisjointPathPair other = (DisjointPathPair) obj; |
| 107 | return Objects.equals(this.src(), other.src()) && |
| 108 | Objects.equals(this.dst(), other.dst()) && |
| 109 | (Objects.equals(this.path1, other.path1) && |
| 110 | Objects.equals(this.path2, other.path2)) || |
| 111 | (Objects.equals(this.path1, other.path2) && |
| 112 | Objects.equals(this.path2, other.path1)); |
| 113 | } |
| 114 | return false; |
| 115 | } |
| 116 | |
| 117 | /** |
| 118 | * Returns number of paths inside this path pair object. |
| 119 | * |
| 120 | * @return number of paths |
| 121 | */ |
| 122 | public int size() { |
| 123 | if (hasBackup()) { |
| 124 | return 2; |
| 125 | } |
| 126 | return 1; |
| 127 | } |
| 128 | } |