/** Visit each predecessor of this node applying the given visitor. Breadth first. */
private <Alpha, Beta> void doVisitPredecessors(
Visitor<Alpha, Beta> visitor, Alpha arg1, Beta arg2, Set<GraphNode> seen) {
if (seen.add(this)) {
Collection<GraphNode> allKill = null;
for (Iterator<GraphNode> i = pred.iterator(); i.hasNext(); ) {
GraphNode pred = i.next();
List<GraphNode> kill = visitor.visit(pred, this, arg1, arg2);
if (kill != null) {
if (allKill == null) allKill = new ArrayList<GraphNode>();
allKill.addAll(kill);
}
}
if (allKill != null) pred.removeAll(allKill);
for (Iterator<GraphNode> i = pred.iterator(); i.hasNext(); ) {
GraphNode pred = i.next();
pred.doVisitPredecessors(visitor, arg1, arg2, seen);
}
}
}
/**
* Return an iterator over all the indirect successors of this node. This does NOT include aliases
* of successors and is used for graph maintenance.
*/
public Iterator<GraphNode> iteratorOverSuccessors() {
return succClosed.iterator();
}
@Override
Iterator<GraphNode> siblingIterator() {
return components.iterator();
}