tom | e348941 | 2014-08-29 02:30:38 -0700 | [diff] [blame] | 1 | package org.onlab.graph; |
| 2 | |
| 3 | import com.google.common.collect.ImmutableList; |
| 4 | |
| 5 | import java.util.Collections; |
| 6 | import java.util.List; |
| 7 | import java.util.Objects; |
| 8 | |
| 9 | import static com.google.common.base.Preconditions.checkArgument; |
| 10 | import static com.google.common.base.Preconditions.checkNotNull; |
| 11 | |
| 12 | /** |
| 13 | * Simple concrete implementation of a directed graph path. |
| 14 | */ |
| 15 | public class DefaultPath<V extends Vertex, E extends Edge<V>> implements Path<V, E> { |
| 16 | |
| 17 | private final V src; |
| 18 | private final V dst; |
| 19 | private final List<E> edges; |
| 20 | private double cost = 0.0; |
| 21 | |
| 22 | /** |
| 23 | * Creates a new path from the specified list of edges and cost. |
| 24 | * |
| 25 | * @param edges list of path edges |
| 26 | * @param cost path cost as a unit-less number |
| 27 | */ |
| 28 | public DefaultPath(List<E> edges, double cost) { |
| 29 | checkNotNull(edges, "Edges list must not be null"); |
| 30 | checkArgument(!edges.isEmpty(), "There must be at least one edge"); |
| 31 | this.edges = ImmutableList.copyOf(edges); |
| 32 | this.src = edges.get(0).src(); |
| 33 | this.dst = edges.get(edges.size() - 1).dst(); |
| 34 | this.cost = cost; |
| 35 | } |
| 36 | |
| 37 | @Override |
| 38 | public V src() { |
| 39 | return src; |
| 40 | } |
| 41 | |
| 42 | @Override |
| 43 | public V dst() { |
| 44 | return dst; |
| 45 | } |
| 46 | |
| 47 | @Override |
| 48 | public double cost() { |
| 49 | return cost; |
| 50 | } |
| 51 | |
| 52 | @Override |
| 53 | public List<E> edges() { |
| 54 | return Collections.unmodifiableList(edges); |
| 55 | } |
| 56 | |
| 57 | @Override |
| 58 | public String toString() { |
| 59 | return com.google.common.base.Objects.toStringHelper(this) |
| 60 | .add("src", src) |
| 61 | .add("dst", dst) |
| 62 | .add("cost", cost) |
| 63 | .add("edges", edges) |
| 64 | .toString(); |
| 65 | } |
| 66 | |
| 67 | @Override |
| 68 | public int hashCode() { |
| 69 | return Objects.hash(src, dst, edges, cost); |
| 70 | } |
| 71 | |
| 72 | @Override |
| 73 | public boolean equals(Object obj) { |
| 74 | if (obj instanceof DefaultPath) { |
| 75 | final DefaultPath other = (DefaultPath) obj; |
tom | 144de69 | 2014-08-29 11:38:44 -0700 | [diff] [blame] | 76 | return Objects.equals(this.src, other.src) && |
tom | e348941 | 2014-08-29 02:30:38 -0700 | [diff] [blame] | 77 | Objects.equals(this.dst, other.dst) && |
| 78 | Objects.equals(this.cost, other.cost) && |
| 79 | Objects.equals(this.edges, other.edges); |
| 80 | } |
| 81 | return false; |
| 82 | } |
| 83 | |
| 84 | } |