private class NodeFinder extends ErrorHandlingSwingWorker<Void, Node> {
@Override
protected Void doInBackground() throws Exception {
BreadthFirstTraverser traverser = new BreadthFirstTraverser(model.getOpposingRoot());
NodeSuggestionStrategy strategy = model.getStrategy();
for (Node targetNode : traverser) {
if (strategy.isCandidate(targetNode)) {
publish(targetNode);
}