09. User Logs - John

public static void main(String[] args) throws IOException {
        BufferedReader rd = new BufferedReader(new InputStreamReader(System.in));

        TreeMap<String, LinkedHashMap<String, int[]>> map = new TreeMap<>();
        String input;

        while (!"end".equals(input = rd.readLine())) {
            String[] info = input.split(" ");
            String IP = info[0].split("=")[1];
            String user = info[2].split("=")[1];

            map.putIfAbsent(user, new LinkedHashMap<>());
            map.get(user).putIfAbsent(IP, new int[1]);
            map.get(user).get(IP)[0]++;
        }

        map.forEach((key, value) -> System.out.printf("%s: %n%s.%n", key, getIPs(value)));
    }

    private static String getIPs(LinkedHashMap<String, int[]> value) {
        return value.entrySet().stream().map(e -> String.format("%s => %d", e.getKey(), e.getValue()[0])).collect(Collectors.joining(", "));
    }