Checks if all the lists representing the values of a hashmap are the same length.

hashmapListsEqualSize.java

    /**
     * Checks if all the lists representing the values of a hashmap are the same length.
     * @param occurrenceFields a hashmap with strings as the keys and lists of strings as the values
     * @return true if all the lists are the same length, false otherwise
     */
    private static boolean checkLengths(HashMap<String, HashMap<String, String>> occurrenceFields) {
        Set<Integer> sizes = new HashSet<Integer>();
        for (HashMap<String, String> list : occurrenceFields.values()) {
            sizes.add(list.size());
        }
        return sizes.size() == 1;
    }