/**
* Method that adds an edge an a node to the path. The new edge to add is given.
*
* @param edge The edge to add to the path.
*/
public void add(Edge edge) {
if (nodePath.isEmpty()) {
add(null, edge);
} else {
add(nodePath.peek(), edge);
}
}
@SuppressWarnings("unchecked")
private void pathSetShortestPath_facilitate(Node current, Path path, List<Path> paths) {
Node source = graph.getNode(this.source_id);
if (current != source) {
Node next = null;
ArrayList<? extends Edge> predecessors =
(ArrayList<? extends Edge>) current.getAttribute(identifier + ".predecessors");
while (current != source && predecessors.size() == 1) {
Edge e = predecessors.get(0);
next = e.getOpposite(current);
path.add(current, e);
current = next;
predecessors =
(ArrayList<? extends Edge>) current.getAttribute(identifier + ".predecessors");
}
if (current != source) {
for (Edge e : predecessors) {
Path p = path.getACopy();
p.add(current, e);
pathSetShortestPath_facilitate(e.getOpposite(current), p, paths);
}
}
}
if (current == source) {
paths.add(path);
}
}
/**
* Returns the shortest path between the source node and one given target. If multiple shortest
* paths exist, one of them is returned at random.
*
* @param target the target of the shortest path starting at the source node given in the
* constructor.
* @return A {@link org.graphstream.graph.Path} object that constrains the list of nodes and edges
* that constitute it.
*/
@SuppressWarnings("unchecked")
public Path getShortestPath(Node target) {
Path p = new Path();
if (target == source) {
return p;
}
boolean noPath = false;
Node v = target;
while (v != source && !noPath) {
ArrayList<? extends Edge> list =
(ArrayList<? extends Edge>) v.getAttribute(identifier + ".predecessors");
if (list == null) {
noPath = true;
} else {
Edge parentEdge = list.get(0);
p.add(v, parentEdge);
v = parentEdge.getOpposite(v);
}
}
return p;
}
/** A synonym for {@link #add(Edge)}. */
public void push(Edge edge) {
add(edge);
}
/** A synonym for {@link #add(Edge)}. */
public void push(Node from, Edge edge) {
add(from, edge);
}