BFS.java

public void bfs(Node rootNode){
        initializeNodes();
        Queue q = new LinkedList();
        q.add(rootNode);
        rootNode.visited=true;
        int parentDistance = 0;
        int parentLevel = 0;
        rootNode.setLevel(parentLevel);
        rootNode.setDistance(parentDistance);
        List<Node> nodeList = new ArrayList<Node>();
        nodeList.add(rootNode);
        nodesSortedByDistance.put(0, nodeList);
        nodesSortedByLevel.put(0, nodeList);
        nodesFound.add(rootNode);
        while(!q.isEmpty()){
            Node n = (Node)q.poll();
            parentLevel = n.getLevel();
            parentDistance = n.getDistance();
            for(Edge edge : n.getNeighbors()){
                Node adj = edge.getNeighbor(n);
                if(!adj.visited){
                    int distance = parentDistance+edge.getWeight();
                    int level = parentLevel + 1;
                    adj.setLevel(level);
                    adj.setDistance(distance);
                    adj.visited=true;
                    q.add(adj);
                    nodesFound.add(adj);
                    if(nodesSortedByDistance.get(distance) == null) {
                        nodeList = new ArrayList<Node>();
                        nodeList.add(adj);
                        nodesSortedByDistance.put(distance, nodeList);
                    } else nodesSortedByDistance.get(distance).add(adj);

                    if(nodesSortedByLevel.get(level) == null) {
                        nodeList = new ArrayList<Node>();
                        nodeList.add(adj);
                        nodesSortedByLevel.put(level, nodeList);
                    }  else nodesSortedByLevel.get(level).add(adj);
                }
            }
        }
    }