private void shortestPathRecur(List<E> edges, int v_a, int v_b) { int k = backtrace[v_a][v_b]; if (k == -1) { E edge = graph.getEdge(vertices.get(v_a), vertices.get(v_b)); if (edge != null) { edges.add(edge); } } else { shortestPathRecur(edges, v_a, k); shortestPathRecur(edges, k, v_b); } }
private GraphPath<V, E> getShortestPathImpl(V a, V b) { int v_a = vertices.indexOf(a); int v_b = vertices.indexOf(b); List<E> edges = new ArrayList<E>(); shortestPathRecur(edges, v_a, v_b); // no path, return null if (edges.size() < 1) { return null; } double weight = 0.; for (E e : edges) { weight += graph.getEdgeWeight(e); } GraphPathImpl<V, E> path = new GraphPathImpl<V, E>(graph, a, b, edges, weight); return path; }