/**
* Follow all edges related to a group of nodes by a given distance.
*
* @param nodes The nodes to start from.
* @param existingNodes
* @param distance The distance to travel.
* @param relatedEdgeModule The related edge module.
*/
public void findLinks(
Collection<DAGNode> nodes,
Collection<DAGNode> existingNodes,
int distance,
RelatedEdgeModule relatedEdgeModule) {
if (distance == 0) return;
// Move through the distance in a breadth-first fashion (level-by-level)
Collection<DAGNode> completed = new HashSet<>(existingNodes);
completed.addAll(nodes);
Collection<DAGNode> currentLevel = nodes;
for (int d = distance; d > 0; d--) {
Collection<DAGNode> nextLevel = new HashSet<>();
// For every node on this level
for (DAGNode n : currentLevel) {
// Find linked edges.
Collection<Edge> relatedEdges = relatedEdgeModule.execute(n, -1, n);
for (Edge e : relatedEdges) {
// Grab every non-predicate argument
Node[] args = e.getNodes();
for (int i = 1; i < args.length; i++) {
// Add to next level if not already looked at
if (args[i] instanceof DAGNode && !completed.contains(args[i]))
nextLevel.add((DAGNode) args[i]);
}
}
}
currentLevel = nextLevel;
// Add all the next level nodes
nodes.addAll(nextLevel);
}
}
private int getAllPaths(Graph g, Vertex s, Vertex d) {
if (s.equals(d)) return 0;
if (g.isDirectEdge(s, d)) return 1;
int count = 0;
for (Edge e : g.getAllEdgesForVertex(s)) {
count += getAllPaths(g, e.getTo(), d);
}
return count;
}
/**
* Finds all edges which involve the nodes as arguments. There cannot be any edges that introduce
* new DAGNodes (though non-DAG nodes are fine). With the exception of introducing predicates that
* define the edge.
*
* @param linkedNodes The nodes that have already been linked up together
* @param toBeLinkedNodes The nodes to be added and linked up.
* @param relatedEdgeModule The Related Edge Module access.
* @return The collection of edges linking these nodes
*/
public Collection<DAGEdge> incorporateNewAndLinkEdges(
Collection<DAGNode> linkedNodes,
Collection<DAGNode> toBeLinkedNodes,
RelatedEdgeModule relatedEdgeModule) {
Collection<DAGEdge> linkedEdges = new HashSet<>();
boolean addPredicate = true;
// Incorporate the new nodes into the linked nodes
linkedNodes.addAll(toBeLinkedNodes);
// Link up the newly incorporated nodes with edges.
Collection<DAGNode> predicates = new HashSet<>();
for (DAGNode newNode : toBeLinkedNodes) {
Collection<Edge> relatedEdges = relatedEdgeModule.execute(newNode, -1, newNode);
// Check every edge
for (Edge e : relatedEdges) {
if (linkedEdges.contains(e)) continue;
Node[] args = e.getNodes();
boolean addEdge = true;
for (int i = 1; i < args.length; i++) {
if (args[i] instanceof DAGNode && !linkedNodes.contains(args[i])) {
addEdge = false;
break;
}
}
if (addEdge) {
if (addPredicate || linkedNodes.contains(args[0])) {
// Add the predicate
if (!linkedNodes.contains(args[0])) predicates.add((DAGNode) args[0]);
linkedEdges.add((DAGEdge) e);
}
}
}
}
// Store predicates as to-be-linked
toBeLinkedNodes.clear();
toBeLinkedNodes.addAll(predicates);
return linkedEdges;
}