code: public static <K, V> Map<K, V> toSorted(Map<K, V> self, Comparator<Map.Entry<K, V>> comparator) {
          List<Map.Entry<K, V>> sortedEntries = toSorted(self.entrySet(), comparator);
          Map<K, V> result = new LinkedHashMap<K, V>();
          for (Map.Entry<K, V> entry : sortedEntries) {
              result.put(entry.getKey(), entry.getValue());
          }
          return result;
      }
docs: Sorts the elements from the given map into a new ordered map using
  the supplied comparator to determine the ordering. The original map is unchanged.
  <pre class="groovyTestCase">
  def keyComparator = [compare: { e1, e2 {@code ->} e1.key {@code <=>} e2.key }] as Comparator
  def valueComparator = [compare: { e1, e2 {@code ->} e1.value {@code <=>} e2.value }] as Comparator
  def map1 = [a:5, b:3, d:4, c:6].toSorted(keyComparator)
  assert map1.toString() == '[a:5, b:3, c:6, d:4]'
  def map2 = [a:5, b:3, d:4, c:6].toSorted(valueComparator)
  assert map2.toString() == '[b:3, d:4, a:5, c:6]'
  </pre>
  
  @param self the original unsorted map
  @param comparator a Comparator used for the comparison
  @return the sorted map
  @since 2.4.0