在List<String>中找出重复的字符串元素__简单高效

public void assertNoDuplicateStr(List<String> list, String key) {
    if (ObjectUtils.isEmpty(list)) {
        return;
    }
    Set<String> set = new HashSet<>();
    list.stream().forEach(e -> Assert.isTrue(set.add(e), String.format("存在重复的%s -> %s", key, e)));
}