*
* @param source list whose elements are to be mapped, or {@code null}
* @param mapFunc mapping function
* @param defaultValue value to be returned if source is {@code null}
* @return a new list, containing mappings of all of the items in the original list
*/
*
* @param source list whose elements are to be mapped, or {@code null}
* @param mapFunc mapping function
* @param defaultValue value to be returned if source is {@code null}
* @return a new list, containing mappings of all of the items in the original list
*/