public static List findCycles(DigraphIteration graph) {
ArrayStack stack = new ArrayStack();
ArrayStack path = new ArrayStack();
Set seen = new HashSet();
List cycles = new ArrayList();
Iterator vertexIterator = graph.vertexIterator();
while (vertexIterator.hasNext()) {
while (vertexIterator.hasNext()) {
Object vertex = vertexIterator.next();
if (seen.add(vertex)) {
stack.push(graph.outgoingIterator(vertex));
path.push(vertex);
break;
}
}
while (!stack.isEmpty()) {
ArcIterator i = (ArcIterator) stack.peek();
Object origin = i.getOrigin();
boolean subtreeIsTraversed = true;
while (i.hasNext()) {
i.next();
Object dst = i.getDestination();
int index = path.indexOf(dst);
if (index < 0) {
seen.add(dst);
stack.push(graph.outgoingIterator(dst));
path.push(dst);
subtreeIsTraversed = false;
break;
} else {
cycles.add(new ArrayList(path.subList(index, path.size())));
}
}
if (subtreeIsTraversed) {
stack.pop();
path.pop();
}
}
}
return cycles;
}
/**
* Peturn parser to pool
*
* @param parser
*/
protected void reuseParser(HtmlParser parser) {
if (null != parser) {
if (parser instanceof NekkoParser) {
synchronized (_xhtmlParsersPool) {
if (_xhtmlParsersPool.size() < STACK_SIZE) {
((NekkoParser) parser).reset();
_xhtmlParsersPool.push(parser);
}
}
}
}
}