private Iterator<Relationship> getRelationshipIterator(
PatternNode fromNode, Node currentNode, PatternRelationship pRel) {
Iterator<Relationship> relItr = null;
if (pRel.anyRelType()) {
relItr = currentNode.getRelationships(pRel.getDirectionFrom(fromNode)).iterator();
} else {
relItr =
currentNode.getRelationships(pRel.getType(), pRel.getDirectionFrom(fromNode)).iterator();
}
return relItr;
}
private boolean traverse(CallPosition callPos) {
// make everything like it was before we returned previous match
PatternPosition currentPos = callPos.getPatternPosition();
PatternRelationship pRel = callPos.getPatternRelationship();
pRel.mark();
visitedRels.remove(callPos.getLastVisitedRelationship());
Node currentNode = currentPos.getCurrentNode();
Iterator<Relationship> relItr = callPos.getRelationshipIterator();
while (relItr.hasNext()) {
Relationship rel = relItr.next();
if (visitedRels.contains(rel)) {
continue;
}
if (!checkProperties(pRel, rel)) {
continue;
}
Node otherNode = rel.getOtherNode(currentNode);
PatternNode otherPosition = pRel.getOtherNode(currentPos.getPatternNode());
pRel.mark();
visitedRels.add(rel);
if (traverse(new PatternPosition(otherNode, otherPosition, pRel, rel, optional), true)) {
callPos.setLastVisitedRelationship(rel);
return true;
}
visitedRels.remove(rel);
pRel.unMark();
}
pRel.unMark();
if (callPos.shouldPopUncompleted()) {
uncompletedPositions.pop();
}
callStack.pop();
foundElements.pop();
return false;
}
private boolean traverse(PatternPosition currentPos, boolean pushElement) {
PatternNode pNode = currentPos.getPatternNode();
Node currentNode = currentPos.getCurrentNode();
if (!checkProperties(pNode, currentNode)) {
return false;
}
if (pushElement) {
foundElements.push(
new PatternElement(
pNode, currentPos.fromPatternRel(),
currentNode, currentPos.fromRelationship()));
}
if (currentPos.hasNext()) {
boolean popUncompleted = false;
PatternRelationship pRel = currentPos.next();
if (currentPos.hasNext()) {
uncompletedPositions.push(currentPos);
popUncompleted = true;
}
assert !pRel.isMarked();
Iterator<Relationship> relItr =
getRelationshipIterator(currentPos.getPatternNode(), currentNode, pRel);
pRel.mark();
while (relItr.hasNext()) {
Relationship rel = relItr.next();
if (visitedRels.contains(rel)) {
continue;
}
if (!checkProperties(pRel, rel)) {
continue;
}
Node otherNode = rel.getOtherNode(currentNode);
PatternNode otherPosition = pRel.getOtherNode(currentPos.getPatternNode());
visitedRels.add(rel);
CallPosition callPos = new CallPosition(currentPos, rel, relItr, pRel, popUncompleted);
callStack.push(callPos);
if (traverse(new PatternPosition(otherNode, otherPosition, pRel, rel, optional), true)) {
return true;
}
callStack.pop();
visitedRels.remove(rel);
}
pRel.unMark();
if (popUncompleted) {
uncompletedPositions.pop();
}
foundElements.pop();
return false;
}
boolean matchFound = true;
if (!uncompletedPositions.isEmpty()) {
PatternPosition digPos = uncompletedPositions.pop();
digPos.reset();
matchFound = traverse(digPos, false);
uncompletedPositions.push(digPos);
return matchFound;
}
return true;
}
