DefaultWeightedEdge addEdge(final Spot source, final Spot target, final double weight) {
if (!graph.containsVertex(source)) {
graph.addVertex(source);
}
if (!graph.containsVertex(target)) {
graph.addVertex(target);
}
final DefaultWeightedEdge edge = graph.addEdge(source, target);
graph.setEdgeWeight(edge, weight);
return edge;
}
/** @see Graph#edgesOf(Object) */
public Set<DefaultWeightedEdge> edgesOf(final Spot spot) {
if (graph.containsVertex(spot)) {
return graph.edgesOf(spot);
} else {
return Collections.emptySet();
}
}