private void DFSUtil(Vertex<Integer> v,Set<Long> visited){
        visited.add(v.getId());
        System.out.print(v.getId() + " ");
        for(Vertex<Integer> vertex : v.getAdjacentVertexes()){
            if(!visited.contains(vertex.getId()))
                DFSUtil(vertex,visited);
        }
    }
http://www.geeksforgeeks.org/breadth-first-traversal-for-a-graph/
http://www.geeksforgeeks.org/depth-first-traversal-for-a-graph/
src/com/interview/graph/GraphTraversal.java