#1557 [java] UnusedNullCheckInEquals false positive when Objects.equals is used

[Slava Semushin]

Latest (5.5.2) PMD complains on this code:

private static boolean isOwner(SeriesDto series) {
    Integer userId = SecurityContextUtils.getUserId();
    return userId != null
        && Objects.equals(
            series.getCreatedBy(),
            userId
        );
}

[INFO] PMD Failure: ru.mystamps.web.controller.SeriesController:481 Rule:UnusedNullCheckInEquals Priority:3 Invoke equals() on the object you've already ensured is not null.

I'm sure that there is no error because I'm checking that first value is not null AND values are equal.

[Andreas Dangel]

Hi,
thanks for reporting.
I think, PMD is suggesting, since you already checked that userId is not null, you should use the equals method of this object:

return userId != null && userId.equals(series.getCreatedBy())

It seems, you can't just use Objects.equals as-is, since you don't want to allow access if both the userId and series.getCreatedBy() would be null.

Does this make sense?