| package org.onlab.graph; |
| |
| import com.google.common.collect.ImmutableList; |
| |
| import java.util.Collections; |
| import java.util.List; |
| import java.util.Objects; |
| |
| import static com.google.common.base.MoreObjects.toStringHelper; |
| import static com.google.common.base.Preconditions.checkArgument; |
| import static com.google.common.base.Preconditions.checkNotNull; |
| |
| /** |
| * Simple concrete implementation of a directed graph path. |
| */ |
| public class DefaultPath<V extends Vertex, E extends Edge<V>> implements Path<V, E> { |
| |
| private final V src; |
| private final V dst; |
| private final List<E> edges; |
| private double cost = 0.0; |
| |
| /** |
| * Creates a new path from the specified list of edges and cost. |
| * |
| * @param edges list of path edges |
| * @param cost path cost as a unit-less number |
| */ |
| public DefaultPath(List<E> edges, double cost) { |
| checkNotNull(edges, "Edges list must not be null"); |
| checkArgument(!edges.isEmpty(), "There must be at least one edge"); |
| this.edges = ImmutableList.copyOf(edges); |
| this.src = edges.get(0).src(); |
| this.dst = edges.get(edges.size() - 1).dst(); |
| this.cost = cost; |
| } |
| |
| @Override |
| public V src() { |
| return src; |
| } |
| |
| @Override |
| public V dst() { |
| return dst; |
| } |
| |
| @Override |
| public double cost() { |
| return cost; |
| } |
| |
| @Override |
| public List<E> edges() { |
| return Collections.unmodifiableList(edges); |
| } |
| |
| @Override |
| public String toString() { |
| return toStringHelper(this) |
| .add("src", src) |
| .add("dst", dst) |
| .add("cost", cost) |
| .add("edges", edges) |
| .toString(); |
| } |
| |
| @Override |
| public int hashCode() { |
| return Objects.hash(src, dst, edges, cost); |
| } |
| |
| @Override |
| public boolean equals(Object obj) { |
| if (obj instanceof DefaultPath) { |
| final DefaultPath other = (DefaultPath) obj; |
| return Objects.equals(this.src, other.src) && |
| Objects.equals(this.dst, other.dst) && |
| Objects.equals(this.cost, other.cost) && |
| Objects.equals(this.edges, other.edges); |
| } |
| return false; |
| } |
| |
| } |