path
Checks whether a path exists between source and sink. DijkstraShortestPath is used instead of org.jgrapht.alg.connectivity.ConnectivityInspector.pathExists, because, in case of directed graph, the latter checks whether the given vertices lay in the same weakly connected component, which is not the desired behavior. As unweighted graphs have a default edge weight of 1.0, shortest path algorithms can always be applied meaningfully.