使用Redis实现签到功能：Java示例解析

在本博客中，我们将讨论一个使用Redis实现的签到功能的Java示例。该示例包括两个主要方法：sign()和signCount()，分别用于用户签到和计算用户当月的签到次数。

1. 签到方法：`sign()`

首先，让我们看看sign()方法：

@Override
public Result sign() {// 1.获取当前登录用户Long userId = UserHolder.getUser().getId();// 2.获取日期LocalDateTime now = LocalDateTime.now();// 3.拼接keyString keySuffix = now.format(DateTimeFormatter.ofPattern(":yyyyMM"));String key = USER_SIGN_KEY + userId + keySuffix;// 4.获取今天是本月第几天int dayOfMonth = now.getDayOfMonth();// 5.写入Redis SETBIT key offset 1stringRedisTemplate.opsForValue().setBit(key, dayOfMonth - 1, true);return Result.ok();
}

2. 计算签到次数方法：`signCount()`

接下来是signCount()方法：

@Override
public Result signCount() {// 1.获取当前登录用户Long userId = UserHolder.getUser().getId();// 2.获取日期LocalDateTime now = LocalDateTime.now();// 3.拼接keyString keySuffix = now.format(DateTimeFormatter.ofPattern(":yyyyMM"));String key = USER_SIGN_KEY + userId + keySuffix;// 4.获取今天是本月第几天int dayOfMonth = now.getDayOfMonth();// 5.获取本月截止到今天的签到次数List<Long> result = stringRedisTemplate.opsForValue().bitField(key, BitFieldSubCommands.create().get(BitFieldSubCommands.BitFieldType.unsigned(dayOfMonth)).valueAt(0));if (result == null || result.isEmpty()) {return Result.ok(0);}Long num = result.get(0);if (num == null || num == 0) {return Result.ok(0);}// 6.循环遍历int count = 0;while (true) {if ((num & 1) == 0) {break;} else {count++;}num >>>= 1;}return Result.ok(count);
}