Lambda删除List中数据

List.removeIf(e -> e.getName().equals("张三"));

Lambda分组排序

reversed倒序

  Map<String, List<User> collectMap = logList.stream()
                .sorted(Comparator.comparing(User::getCreateTime).reversed())
                .collect(Collectors.groupingBy(User::getUserName));

Lambda取每个key的第一条数据

List<AfinApprovalLog> tempList = new ArrayList<>();
        collectMap.forEach((key ,value) -> {
            tempList.add(value.get(0));
        });

Lambda取交集

 //取交集
        List<User> innerList = tempList.stream()
                .filter(m -> userList.stream().map(d -> d.getUserName()).collect(Collectors.toList())
                        .contains(m.getUserName())).collect(Collectors.toList());