I hope all is good for you.

I have two maps and I want to keep null values. I know that merge function can’t manage null values but I need to keep null data and use the Binary Operation.

How I can manage my code to avoid NPE.

  private Map<String, Object> mergeMaps(
      Map<String, Object> map1, Map<String, Object> map2) {
    return Stream.of(map1, map2)
        .map(Map::entrySet)
        .flatMap(Collection::stream)
        .collect(
            Collectors.toMap(
                Map.Entry::getKey,
                Map.Entry::getValue,
                (v1, v2) -> StringUtils.isNotEmpty(v1.toString()) ? v1 : v2;
                ));
  }

Thanks a lot.