java8拉姆达表达式对Object去重复

public static <T> Predicate<T> distinctByKey(Function<? super T, Object> keyExtractor) {Map<Object, Boolean> seen = new ConcurrentHashMap<>();return object -> seen.putIfAbsent(keyExtractor.apply(object),Boolean.TRUE) == null;}public static void main(String[] args) {List<EarlyChange> list = new ArrayList<EarlyChange>();EarlyChange eChange = new EarlyChange("电流",1);EarlyChange eChange1 = new EarlyChange("烟雾",8);EarlyChange eChange2 = new EarlyChange("温度",5);EarlyChange eChange3 = new EarlyChange("电气火灾",7);EarlyChange eChange4 = new EarlyChange("电气火灾",8);list.add(eChange);list.add(eChange1);list.add(eChange2);list.add(eChange3);list.add(eChange4);//java8拉姆达表达式对Object去重复List<EarlyChange> collect = list.stream().filter(distinctByKey(EarlyChange::getName )).collect(Collectors.toList());for (EarlyChange earlyChange : collect) {System.out.println(earlyChange);}}

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