MoreMapUtils.java 文件源码

private static <T> List<T> getList(
    Map<?, ?> map,
    Object key,
    List<T> defaultValue,
    Function<Object, T> transformation) {
  Object value = map.get(key);
  if (value == null) {
    return defaultValue;
  }

  if (value instanceof String) {
    value = Splitter.on(',').splitToList(value.toString());
  }

  if (!(value instanceof Collection)) {
    return Collections.singletonList(transformation.apply(value));
  }

  return FluentIterable.from((Collection<?>) value).transform(transformation).toList();
}