code: public Map<String, Object> fromJson(Reader reader) throws IOException {
      if (reader == null) {
        throw new IllegalArgumentException("reader == null");
      }
      JsonReader jsonReader = new JsonReader(reader);
      jsonReader.setLenient(isLenient);
      try {
        return readerToMap(jsonReader);
      } finally {
        reader.close();
      }
    }
docs: Deserializes the json read from the specified {@link Reader} into a {@link Map}. If you have
  the Json in a String form instead of a {@link Reader}, use {@link #fromJson(String)} instead.