集合对象去重时报空指针异常

Question

集合对象去重

List battleArrayPlayerList = playList.stream().collect(Collectors.collectingAndThen(
Collectors.toCollection(() -> new TreeSet<>(Comparator.comparing(BattleArrayPlayer::getPlayerId))),
ArrayList::new));

上面这行代码报空指针

求解答！

Answer 1

BattleArrayPlayer对象集合中的playerId是不是有空的？