public class Test{

    private static Map<String, Boolean> finalMap = new HashMap<>();

    private static void createReport(int searchDepth, String prevKey, List<HRBOPresenceStatus> onlineStatuses) {
        Map<String, List<HRBOPresenceStatus>> map = new HashMap<>();
        for (HRBOPresenceStatus status : onlineStatuses) {
            String key = prevKey.length() > 0 ? prevKey + ", " + status.getValue(searchDepth) : status.getValue(searchDepth);
            if (map.get(key) == null) {
                List<HRBOPresenceStatus> list = new ArrayList<>();
                list.add(status);
                map.put(key, list);
            } else {
                map.get(key).add(status);
            }
        }

        for (Map.Entry<String, List<HRBOPresenceStatus>> entry : map.entrySet()) {
            if (entry.getValue().size() != 1) {
                createReport(searchDepth + 1, entry.getKey(), entry.getValue());
            } else {
                finalMap.put(entry.getKey(), entry.getValue().get(0).isOnline());
            }
        }
    }
}