public void load(File file){
	if ( !file.exists() ){
	    System.out.println(file + " not found");
	    return;
	}
	BufferedReader data;
	System.out.println("Loading....");
	try{
	    data = new BufferedReader(new FileReader(file));
	    while (true){
		String line = data.readLine();
		if (line==null) {break;}
		String[] pair = line.split("\t");
		String host = pair[0];
		int IP = stringToIP(pair[1]);
		hostNames.put(IP, host);
		ipAddresses.put(host, IP);
	    }
	} catch(IOException e){System.out.println("Fail: " + e);}
	System.out.println("Loading Done");
    }