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fix code
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Looly
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1ff0dcde0f
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5bf7dcf88e
@ -15,7 +15,6 @@ package org.dromara.hutool.core.data.id;
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import org.dromara.hutool.core.date.SystemClock;
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import org.dromara.hutool.core.lang.Assert;
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import org.dromara.hutool.core.lang.tuple.Pair;
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import org.dromara.hutool.core.text.StrUtil;
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import org.dromara.hutool.core.util.RandomUtil;
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import java.io.Serializable;
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@ -53,11 +52,6 @@ public class Snowflake implements Serializable {
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* 默认的起始时间，为Thu, 04 Nov 2010 01:42:54 GMT
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*/
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public static long DEFAULT_TWEPOCH = 1288834974657L;
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/**
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* 默认回拨时间，2S
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*/
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public static long DEFAULT_TIME_OFFSET = 2000L;
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private static final long WORKER_ID_BITS = 5L;
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// 最大支持机器节点数0~31，一共32个
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@SuppressWarnings({"PointlessBitwiseExpression", "FieldCanBeLocal"})
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@ -84,10 +78,6 @@ public class Snowflake implements Serializable {
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private final long workerId;
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private final long dataCenterId;
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private final boolean useSystemClock;
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/**
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* 允许的时钟回拨毫秒数
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*/
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private final long timeOffset;
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/**
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* 当在低频模式下时，序号始终为0，导致生成ID始终为偶数<br>
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* 此属性用于限定一个随机上限，在不同毫秒下生成序号时，给定一个随机数，避免偶数问题。<br>
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@ -146,20 +136,9 @@ public class Snowflake implements Serializable {
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* @param isUseSystemClock 是否使用{@link SystemClock} 获取当前时间戳
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* @since 5.1.3
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*/
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public Snowflake(final Date epochDate, final long workerId, final long dataCenterId, final boolean isUseSystemClock) {
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this(epochDate, workerId, dataCenterId, isUseSystemClock, DEFAULT_TIME_OFFSET);
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}
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/**
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* @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
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* @param workerId 工作机器节点id
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* @param dataCenterId 数据中心id
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* @param isUseSystemClock 是否使用{@link SystemClock} 获取当前时间戳
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* @param timeOffset 允许时间回拨的毫秒数
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* @since 5.8.0
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*/
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public Snowflake(final Date epochDate, final long workerId, final long dataCenterId, final boolean isUseSystemClock, final long timeOffset) {
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this(epochDate, workerId, dataCenterId, isUseSystemClock, timeOffset, 0);
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public Snowflake(final Date epochDate, final long workerId, final long dataCenterId,
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final boolean isUseSystemClock) {
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this(epochDate, workerId, dataCenterId, isUseSystemClock, 0);
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}
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/**
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@ -167,17 +146,15 @@ public class Snowflake implements Serializable {
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* @param workerId 工作机器节点id
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* @param dataCenterId 数据中心id
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* @param isUseSystemClock 是否使用{@link SystemClock} 获取当前时间戳
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* @param timeOffset 允许时间回拨的毫秒数
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* @param randomSequenceLimit 限定一个随机上限，在不同毫秒下生成序号时，给定一个随机数，避免偶数问题，0表示无随机，上限不包括值本身。
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* @since 5.8.0
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*/
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public Snowflake(final Date epochDate, final long workerId, final long dataCenterId,
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final boolean isUseSystemClock, final long timeOffset, final long randomSequenceLimit) {
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final boolean isUseSystemClock, final long randomSequenceLimit) {
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this.twepoch = (null != epochDate) ? epochDate.getTime() : DEFAULT_TWEPOCH;
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this.workerId = Assert.checkBetween(workerId, 0, MAX_WORKER_ID);
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this.dataCenterId = Assert.checkBetween(dataCenterId, 0, MAX_DATA_CENTER_ID);
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this.useSystemClock = isUseSystemClock;
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this.timeOffset = timeOffset;
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this.randomSequenceLimit = Assert.checkBetween(randomSequenceLimit, 0, SEQUENCE_MASK);
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}
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@ -219,19 +196,16 @@ public class Snowflake implements Serializable {
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public synchronized long nextId() {
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long timestamp = genTime();
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if (timestamp < this.lastTimestamp) {
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if (this.lastTimestamp - timestamp < timeOffset) {
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// 容忍指定的回拨，避免NTP校时造成的异常
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timestamp = lastTimestamp;
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} else {
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// 如果服务器时间有问题(时钟后退) 报错。
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throw new IllegalStateException(StrUtil.format("Clock moved backwards. Refusing to generate id for {}ms", lastTimestamp - timestamp));
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}
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timestamp = lastTimestamp;
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}
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if (timestamp == this.lastTimestamp) {
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// 时间出现回拨，递增序号
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final long sequence = (this.sequence + 1) & SEQUENCE_MASK;
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if (sequence == 0) {
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timestamp = tilNextMillis(lastTimestamp);
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// 如果序号耗尽，不再等待时间追赶，而是采用“超前消费”方式，让时间递增。
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// 这样可以避免系统暂停等待，而选择在“未来”ID新增不快时追上来。
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timestamp += 1;
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}
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this.sequence = sequence;
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} else {
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@ -295,27 +269,6 @@ public class Snowflake implements Serializable {
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}
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// ------------------------------------------------------------------------------------------------------------------------------------ Private method start
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/**
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* 循环等待下一个时间
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*
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* @param lastTimestamp 上次记录的时间
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* @return 下一个时间
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*/
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private long tilNextMillis(final long lastTimestamp) {
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long timestamp = genTime();
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// 循环直到操作系统时间戳变化
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while (timestamp == lastTimestamp) {
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timestamp = genTime();
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}
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if (timestamp < lastTimestamp) {
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// 如果发现新的时间戳比上次记录的时间戳数值小，说明操作系统时间发生了倒退，报错
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throw new IllegalStateException(
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StrUtil.format("Clock moved backwards. Refusing to generate id for {}ms", lastTimestamp - timestamp));
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}
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return timestamp;
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}
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/**
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* 生成时间戳
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*
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@ -94,7 +94,7 @@ public class SnowflakeTest {
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@Disabled
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public void snowflakeRandomSequenceTest(){
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final Snowflake snowflake = new Snowflake(null, 0, 0,
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false, Snowflake.DEFAULT_TIME_OFFSET, 2);
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false, 2);
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for (int i = 0; i < 1000; i++) {
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final long id = snowflake.nextId();
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Console.log(id);
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@ -107,7 +107,7 @@ public class SnowflakeTest {
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public void uniqueOfRandomSequenceTest(){
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// 测试并发环境下生成ID是否重复
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final Snowflake snowflake = new Snowflake(null, 0, 0,
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false, Snowflake.DEFAULT_TIME_OFFSET, 100);
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false, 100);
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final Set<Long> ids = new ConcurrentHashSet<>();
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ThreadUtil.concurrencyTest(100, () -> {
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