code: public <K, V> SortedMap<K, V> subMap(SortedMap<K, V> map, 
                                           K fromKey, K toKey) {
          return map.subMap(fromKey, toKey);
      }
docs: Get a portion of the given sorted map from the given fromKey, inclusive,
  up to, but excluding, the given toKey. The keys are based on the sort
  algorithm of the keys in the given map.
  
  @param <K> The component type of the keys
  @param <V> The component type of the values
  
  @param map The map to retrieve from
  @param fromKey The key to start from, inclusive
  @param toKey The key to end at, exclusive
  
  @return The portion of the map from the from key to the end key
  
  @see SortedMap#subMap(Object, Object)