when compare two json field about null and empty string "", the zjsonpatch is unexcept

[shengqianfeng]

`

    final String newData = "{}";

    final String oldData = "{\"x\": \"\"}";

   JsonNode oldJson = OBJECT_MAPPER.readTree(StringUtils.isEmpty(oldData) ? "{}" : oldData);

    JsonNode newJson = OBJECT_MAPPER.readTree(StringUtils.isEmpty(newData) ? "{}" : newData);

     final EnumSet<DiffFlags> enumSet = EnumSet.of(DiffFlags.ADD_ORIGINAL_VALUE_ON_REPLACE);

     JsonNode jsonNode = JsonDiff.asJson(oldJson, newJson, enumSet);

`
the op filed of result is: remove ----this is right.
the value filed of result is: "" -----this is not right , i think the right value is null. beacuse the "value" of result should represent new value.