public HashMap<String, Integer> calculateDocumentOccuriences(
			List<String> unique, List<List<String>> documents)
			throws InvalidFormatException, IOException {

		HashMap<String, Integer> map = new HashMap<>();

		for (String uniqueToken : unique) {
			map.put(uniqueToken, 0);
			for (List<String> list : documents) {
				primaryLoop: for (int i = 0; i < list.size(); i++) {
					if (list.get(i).equals(uniqueToken)) {
						int occ = map.get(uniqueToken);
						occ++;
						map.put(uniqueToken, occ); //
						break primaryLoop;
					}
				}
			}
		}

		return map;

	}