public static void main(String[] args) throws Exception {
		File activeUsers = new File("activeUser.txt");
		if (!activeUsers.exists()) {
			System.exit(0);
		}
		GraphIndexing graphIndexing = new GraphIndexing(activeUsers);
		TreeMap<Integer, UserFollowers> map = graphIndexing.buildMap();
		System.out.println("buildMap finished .. start writing map with size: "
				+ map.size());
		writeHashMap("graphMap", map);
	}