code: public static <K, V> Map<K, V> nullToEmptyMap(Map<K, V> newValue) {
      if (newValue == null) {
        return new HashMap<>();
      }
      return newValue;
    }
docs: Returns an empty map if the input is null
  
  @param newValue - nullable map value
  @param <K>      - map key
  @param <V>      - map value
  @return non-null Map