全局Id生成器
为了增加id的安全性,我们可以不直接使用redis自增生成的数值,可以拼接一些其他的数值
id的组成部分
- 符号位:1bit,永远为0
- 时间戳:31bit,以秒为单位,可以使用69年
- 序列号:32bit,秒内的计数器,支持每秒产生2^32个不同的id
代码具体实现
点击查看代码
package com.waa.gulimall.order.util;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.data.redis.core.RedisTemplate;
import org.springframework.data.redis.core.StringRedisTemplate;
import org.springframework.stereotype.Component;
import java.time.LocalDateTime;
import java.time.ZoneOffset;
import java.time.format.DateTimeFormatter;
@Component
public class RedisIdWoker {
@Autowired
private StringRedisTemplate stringRedisTemplate;
private static final long BEGIN_TIMESTAMP = 1674220484L;
private static final int COUNT_BIT = 32;
public long nextId(String keyPrefix){
//1.生成时间戳
final LocalDateTime localDateTime = LocalDateTime.now();
final long nowTime = localDateTime.toEpochSecond(ZoneOffset.UTC);
long timestamp = nowTime - BEGIN_TIMESTAMP;
final String format = localDateTime.format(DateTimeFormatter.ofPattern("yyyy:MM:dd"));
//2.生成序列号
final Long increment = stringRedisTemplate.opsForValue().increment("icr:" + keyPrefix + ":" + format);
return timestamp << COUNT_BIT | increment;
}
public static void main(String[] args) {
final LocalDateTime now = LocalDateTime.now();
System.out.println(now.toEpochSecond(ZoneOffset.UTC));
}
}