springboot项目Redis统计在线用户的实现示例

@Override
    public void markUserActive(int userId) {
        String key = "active_users:" + LocalDateTime.now().format(DateTimeFormatter.ISO_LOCAL_DATE_TIME);
        redisUtils.setBit(key, userId, true);
        // 设置2小时的过期时间
        redisUtils.expire(key, 2, TimeUnit.HOURS);
    }

@Override
    public List<Integer> getActiveUserIds() {
        List<Integer> activeUserIds = new ArrayList<>();

        // 当前时间
        LocalDateTime currentTime = LocalDateTime.now();
        for (int i = 0; i < 2; i++) {
            // 遍历过去2小时内的键
            String key = "active_users:" + currentTime.minusHours(i).format(DateTimeFormatter.ISO_LOCAL_DATE_TIME);

            if (redisUtils.hasKey(key)) {
                // 遍历1000个用户
                for (int j = 0; j < 1000; j++) {
                    Boolean isUserActive = redisUtils.getBit(key, j);
                    if (isUserActive != null && isUserActive) {
                        activeUserIds.add(j);
                    }
                }
            }
        }

        return activeUserIds;
    }

String key = "active_users:" + LocalDateTime.now().truncatedTo(ChronoUnit.MINUTES).format(DateTimeFormatter.ISO_LOCAL_DATE_TIME);