mirror of
https://gitee.com/chinabugotech/hutool.git
synced 2025-05-09 23:51:34 +08:00
pr#95
This commit is contained in:
Looly
parent
0ce06fbd30
commit
7cd260c1ea
@ -8,6 +8,7 @@
|
||||
### 新特性
|
||||
* 【core 】 废弃isMactchRegex，改为isMatchRegex（方法错别字）
|
||||
* 【core 】 修正hasNull()方法上注释错误（issue#I18TAG@Gitee）
|
||||
* 【core 】 Snowflake的起始时间可以被指定（pr#95@Gitee）
|
||||
### Bug修复
|
||||
* 【core 】 CharsetUtil在不支持GBK的系统中运行报错问题（issue#731@Github）
|
||||
* 【core 】 RandomUtil的randomEleSet方法顺序不随机的问题（pr#741@Github）
|
||||
|
||||
@ -1,104 +1,108 @@
|
||||
package cn.hutool.core.lang;
|
||||
|
||||
import cn.hutool.core.date.SystemClock;
|
||||
import cn.hutool.core.util.StrUtil;
|
||||
|
||||
import java.io.Serializable;
|
||||
import java.util.Date;
|
||||
|
||||
import cn.hutool.core.date.DateUtil;
|
||||
import cn.hutool.core.date.SystemClock;
|
||||
import cn.hutool.core.util.StrUtil;
|
||||
|
||||
/**
|
||||
* Twitter的Snowflake 算法<br>
|
||||
* 分布式系统中，有一些需要使用全局唯一ID的场景，有些时候我们希望能使用一种简单一些的ID，并且希望ID能够按照时间有序生成。
|
||||
*
|
||||
*
|
||||
* <p>
|
||||
* snowflake的结构如下(每部分用-分开):<br>
|
||||
*
|
||||
*
|
||||
* <pre>
|
||||
* 0 - 0000000000 0000000000 0000000000 0000000000 0 - 00000 - 00000 - 000000000000
|
||||
* </pre>
|
||||
*
|
||||
* <p>
|
||||
* 第一位为未使用(符号位表示正数)，接下来的41位为毫秒级时间(41位的长度可以使用69年)<br>
|
||||
* 然后是5位datacenterId和5位workerId(10位的长度最多支持部署1024个节点）<br>
|
||||
* 最后12位是毫秒内的计数（12位的计数顺序号支持每个节点每毫秒产生4096个ID序号）
|
||||
*
|
||||
* <p>
|
||||
* 并且可以通过生成的id反推出生成时间,datacenterId和workerId
|
||||
* <p>
|
||||
* 参考：http://www.cnblogs.com/relucent/p/4955340.html
|
||||
*
|
||||
*
|
||||
* @author Looly
|
||||
* @since 3.0.1
|
||||
*/
|
||||
public class Snowflake implements Serializable{
|
||||
public class Snowflake implements Serializable {
|
||||
private static final long serialVersionUID = 1L;
|
||||
|
||||
// Thu, 04 Nov 2010 01:42:54 GMT
|
||||
private long twepoch = 1288834974657L;
|
||||
private final long twepoch;
|
||||
private final long workerIdBits = 5L;
|
||||
private final long datacenterIdBits = 5L;
|
||||
private final long dataCenterIdBits = 5L;
|
||||
//// 最大支持机器节点数0~31，一共32个
|
||||
private final long maxWorkerId = -1L ^ (-1L << workerIdBits);
|
||||
// 最大支持数据中心节点数0~31，一共32个
|
||||
private final long maxDatacenterId = -1L ^ (-1L << datacenterIdBits);
|
||||
@SuppressWarnings({"PointlessBitwiseExpression", "FieldCanBeLocal"})
|
||||
private final long maxWorkerId = -1L ^ (-1L << workerIdBits);
|
||||
@SuppressWarnings({"PointlessBitwiseExpression", "FieldCanBeLocal"})
|
||||
private final long maxDataCenterId = -1L ^ (-1L << dataCenterIdBits);
|
||||
// 序列号12位
|
||||
private final long sequenceBits = 12L;
|
||||
// 机器节点左移12位
|
||||
private final long workerIdShift = sequenceBits;
|
||||
// 数据中心节点左移17位
|
||||
private final long datacenterIdShift = sequenceBits + workerIdBits;
|
||||
private final long dataCenterIdShift = sequenceBits + workerIdBits;
|
||||
// 时间毫秒数左移22位
|
||||
private final long timestampLeftShift = sequenceBits + workerIdBits + datacenterIdBits;
|
||||
private final long timestampLeftShift = sequenceBits + workerIdBits + dataCenterIdBits;
|
||||
@SuppressWarnings({"PointlessBitwiseExpression", "FieldCanBeLocal"})
|
||||
private final long sequenceMask = -1L ^ (-1L << sequenceBits);// 4095
|
||||
|
||||
private long workerId;
|
||||
private long datacenterId;
|
||||
private long dataCenterId;
|
||||
private long sequence = 0L;
|
||||
private long lastTimestamp = -1L;
|
||||
private boolean useSystemClock;
|
||||
|
||||
/**
|
||||
* 构造
|
||||
*
|
||||
* @param workerId 终端ID
|
||||
* @param datacenterId 数据中心ID
|
||||
*
|
||||
* @param workerId 终端ID
|
||||
* @param dataCenterId 数据中心ID
|
||||
*/
|
||||
public Snowflake(long workerId, long datacenterId) {
|
||||
this(workerId, datacenterId, false);
|
||||
public Snowflake(long workerId, long dataCenterId) {
|
||||
this(workerId, dataCenterId, false);
|
||||
}
|
||||
|
||||
/**
|
||||
* 构造
|
||||
*
|
||||
* @param workerId 终端ID
|
||||
* @param datacenterId 数据中心ID
|
||||
*
|
||||
* @param workerId 终端ID
|
||||
* @param dataCenterId 数据中心ID
|
||||
* @param isUseSystemClock 是否使用{@link SystemClock} 获取当前时间戳
|
||||
*/
|
||||
public Snowflake(long workerId, long datacenterId, boolean isUseSystemClock) {
|
||||
public Snowflake(long workerId, long dataCenterId, boolean isUseSystemClock) {
|
||||
this(null, workerId, dataCenterId, isUseSystemClock);
|
||||
}
|
||||
|
||||
/**
|
||||
* @param epochDate 初始化时间起点（null表示默认起始日期）,后期修改会导致id重复,如果要修改连workerId dataCenterId，慎用
|
||||
* @param workerId 工作机器节点id
|
||||
* @param dataCenterId 数据中心id
|
||||
* @param isUseSystemClock 是否使用{@link SystemClock} 获取当前时间戳
|
||||
* @since 5.1.3
|
||||
*/
|
||||
public Snowflake(Date epochDate, long workerId, long dataCenterId, boolean isUseSystemClock) {
|
||||
if (null != epochDate) {
|
||||
this.twepoch = epochDate.getTime();
|
||||
} else{
|
||||
// Thu, 04 Nov 2010 01:42:54 GMT
|
||||
this.twepoch = 1288834974657L;
|
||||
}
|
||||
if (workerId > maxWorkerId || workerId < 0) {
|
||||
throw new IllegalArgumentException(StrUtil.format("worker Id can't be greater than {} or less than 0", maxWorkerId));
|
||||
}
|
||||
if (datacenterId > maxDatacenterId || datacenterId < 0) {
|
||||
throw new IllegalArgumentException(StrUtil.format("datacenter Id can't be greater than {} or less than 0", maxDatacenterId));
|
||||
if (dataCenterId > maxDataCenterId || dataCenterId < 0) {
|
||||
throw new IllegalArgumentException(StrUtil.format("datacenter Id can't be greater than {} or less than 0", maxDataCenterId));
|
||||
}
|
||||
this.workerId = workerId;
|
||||
this.datacenterId = datacenterId;
|
||||
this.dataCenterId = dataCenterId;
|
||||
this.useSystemClock = isUseSystemClock;
|
||||
}
|
||||
/**
|
||||
*
|
||||
* @param epochStr 初始化时间起点 后期修改会导致id重复,如果要修改连workerId datacenterId 一起修改 慎用,格式yyyyMMdd，
|
||||
* @param workerId 工作机器节点id
|
||||
* @param datacenterId 数据中心id
|
||||
* @param isUseSystemClock 是否使用{@link SystemClock} 获取当前时间戳
|
||||
*/
|
||||
public Snowflake(String epochStr, long workerId, long datacenterId, boolean isUseSystemClock) {
|
||||
this(workerId, datacenterId, isUseSystemClock);
|
||||
Date d=DateUtil.parse(epochStr, "yyyyMMdd");
|
||||
long twepoch=d.getTime();
|
||||
if(twepoch>this.twepoch){
|
||||
this.twepoch=twepoch;
|
||||
}
|
||||
}
|
||||
|
||||
/**
|
||||
* 根据Snowflake的ID，获取机器id
|
||||
*
|
||||
@ -116,11 +120,11 @@ public class Snowflake implements Serializable{
|
||||
* @return 所属数据中心
|
||||
*/
|
||||
public long getDataCenterId(long id) {
|
||||
return id >> datacenterIdShift & ~(-1L << datacenterIdBits);
|
||||
return id >> dataCenterIdShift & ~(-1L << dataCenterIdBits);
|
||||
}
|
||||
|
||||
/**
|
||||
*根据Snowflake的ID，获取生成时间
|
||||
* 根据Snowflake的ID，获取生成时间
|
||||
*
|
||||
* @param id snowflake算法生成的id
|
||||
* @return 生成的时间
|
||||
@ -131,7 +135,7 @@ public class Snowflake implements Serializable{
|
||||
|
||||
/**
|
||||
* 下一个ID
|
||||
*
|
||||
*
|
||||
* @return ID
|
||||
*/
|
||||
public synchronized long nextId() {
|
||||
@ -151,9 +155,9 @@ public class Snowflake implements Serializable{
|
||||
|
||||
lastTimestamp = timestamp;
|
||||
|
||||
return ((timestamp - twepoch) << timestampLeftShift) | (datacenterId << datacenterIdShift) | (workerId << workerIdShift) | sequence;
|
||||
return ((timestamp - twepoch) << timestampLeftShift) | (dataCenterId << dataCenterIdShift) | (workerId << workerIdShift) | sequence;
|
||||
}
|
||||
|
||||
|
||||
/**
|
||||
* 下一个ID（字符串形式）
|
||||
*
|
||||
@ -164,9 +168,10 @@ public class Snowflake implements Serializable{
|
||||
}
|
||||
|
||||
// ------------------------------------------------------------------------------------------------------------------------------------ Private method start
|
||||
|
||||
/**
|
||||
* 循环等待下一个时间
|
||||
*
|
||||
*
|
||||
* @param lastTimestamp 上次记录的时间
|
||||
* @return 下一个时间
|
||||
*/
|
||||
@ -180,7 +185,7 @@ public class Snowflake implements Serializable{
|
||||
|
||||
/**
|
||||
* 生成时间戳
|
||||
*
|
||||
*
|
||||
* @return 时间戳
|
||||
*/
|
||||
private long genTime() {
|
||||
|
||||
Loading…
x
Reference in New Issue
Block a user