public static void saveGraph(Graph g, File f) throws FileNotFoundException, SecurityException {
ArrayList<GraphEdge> edgemarks = new ArrayList<GraphEdge>();
PrintStream p = new PrintStream(new FileOutputStream(f));
try {
Iterator<GraphNode> n = g.getNodeIterator();
int count = 1;
while (n.hasNext()) {
GraphNode node = n.next();
ListIterator<GraphEdge> e = node.getEdgeIterator();
while (e.hasNext()) {
GraphEdge edge = e.next();
if (g.getNodeById(edge.getTarget().getId()) == null) {
e.remove();
continue;
}
if (!edgemarks.contains(edge))
p.println(
""
+ (node.getId() + 1)
+ " "
+ (edge.getTarget().getId() + 1)
+ " "
+ edge.getWeight());
edgemarks.add(edge.getTarget().getEdgeByTargetId(node.getId()));
edgemarks.add(edge);
}
if (count % 100 == 0) System.out.println("Saving. . ." + count++);
}
} finally {
p.close();
}
}
public ShortestPaths(Graph g, GraphNode x) throws NegativeEdgeException {
this.g = g;
Iterator<GraphNode> i = g.getNodeIterator();
while (i.hasNext()) {
nodedata.put(i.next(), new SPData());
}
generateShortestPathsFrom(x);
}
static GraphId[] getOrderedIds(Graph g) {
List idList = new ArrayList();
for (Iterator i = g.getNodeIterator(); i.hasNext(); ) {
GraphId id = (GraphId) i.next();
idList.add(id.toString());
}
GraphId[] result = (GraphId[]) idList.toArray(new GraphId[idList.size()]);
Arrays.sort(result);
return result;
}
static String[] getOrderedEdgeLabels(Graph g) {
Set labelSet = new HashSet();
for (Iterator i = g.getNodeIterator(); i.hasNext(); ) {
GraphId id = (GraphId) i.next();
labelSet.addAll(g.getEdgeLabels(id));
}
log.debug(labelSet.size() + " labels in labelset.");
String[] result = (String[]) labelSet.toArray(new String[labelSet.size()]);
Arrays.sort(result);
return result;
}
private void generateShortestPathsFrom(GraphNode source) throws NegativeEdgeException {
Iterator<GraphNode> l = g.getNodeIterator();
ListIterator<GraphEdge> m;
FibonacciHeap<GraphNode> h = new FibonacciHeap<GraphNode>();
GraphNode t, v;
GraphEdge e;
h.insert(source, 0);
data(source).setPrev(null);
data(source).setIncidentEdge(null);
this.source = source;
while (l.hasNext()) {
t = l.next();
if (t == source) continue;
data(t).setPrev(null);
data(t).setIncidentEdge(null);
h.insert(t, Integer.MAX_VALUE);
}
while (!h.isEmpty()) {
t = h.extractMin();
m = t.getEdgeIterator();
while (m.hasNext()) {
e = m.next();
if (g.getNodeById(e.getTarget().getId()) == null) {
m.remove();
continue;
}
if (e.getWeight() < 0) {
throw new NegativeEdgeException(
"Dijkstra's algorithm won't work on graphs with negative edge weights!");
}
v = e.getTarget();
if (h.getKey(v) > h.getKey(t) + e.getWeight()) {
try {
h.decreaseKey(v, h.getKey(t) + e.getWeight());
} catch (KeyNotLessException x) {
// can't happen!
}
data(v).setPrev(t);
data(v).setIncidentEdge(e);
}
}
}
}
