- public Map<String, List<String>> getAuthorsGrouped() throws IOException {
- int MAX = 20;
-
- Map<String, List<String>> groups = new TreeMap<String, List<String>>();
- List<String> authors = getAuthors();
-
- // If all authors fit the max, just report them as is
- if (authors.size() <= MAX) {
- groups.put("", authors);
- return groups;
- }
-
- // Create groups A to Z, which can be empty here
- for (char car = 'A'; car <= 'Z'; car++) {
- groups.put(Character.toString(car), getAuthorsGroup(authors, car));
- }
-
- // Collapse them
- List<String> keys = new ArrayList<String>(groups.keySet());
- for (int i = 0; i + 1 < keys.size(); i++) {
- String keyNow = keys.get(i);
- String keyNext = keys.get(i + 1);
-
- List<String> now = groups.get(keyNow);
- List<String> next = groups.get(keyNext);
-
- int currentTotal = now.size() + next.size();
- if (currentTotal <= MAX) {
- String key = keyNow.charAt(0) + "-"
- + keyNext.charAt(keyNext.length() - 1);
-
- List<String> all = new ArrayList<String>();
- all.addAll(now);
- all.addAll(next);
-
- groups.remove(keyNow);
- groups.remove(keyNext);
- groups.put(key, all);
-
- keys.set(i, key); // set the new key instead of key(i)
- keys.remove(i + 1); // remove the next, consumed key
- i--; // restart at key(i)
- }
- }
-
- // Add "special" groups
- groups.put("*", getAuthorsGroup(authors, '*'));
- groups.put("0-9", getAuthorsGroup(authors, '0'));
-
- // Prune empty groups
- keys = new ArrayList<String>(groups.keySet());
- for (String key : keys) {
- if (groups.get(key).isEmpty()) {
- groups.remove(key);
- }
- }
-
- return groups;