org.apache.shardingsphere.core.strategy.keygen

Class SnowflakeShardingKeyGenerator

java.lang.Object

org.apache.shardingsphere.core.strategy.keygen.SnowflakeShardingKeyGenerator

All Implemented Interfaces:

ShardingKeyGenerator, TypeBasedSPI

public final class SnowflakeShardingKeyGenerator
extends Object
implements ShardingKeyGenerator

Snowflake distributed primary key generator.

Use snowflake algorithm. Length is 64 bit.

 1bit sign bit.
 41bits timestamp offset from 2016.11.01(ShardingSphere distributed primary key published data) to now.
 10bits worker process id.
 12bits auto increment offset in one mills
 

Call @SnowflakeShardingKeyGenerator.setWorkerId to set worker id, default value is 0.

Call @SnowflakeShardingKeyGenerator.setMaxTolerateTimeDifferenceMilliseconds to set max tolerate time difference milliseconds, default value is 0.

Author:

gaohongtao, panjuan

Field Summary

Fields

Modifier and Type	Field and Description
static long	EPOCH

Constructor Summary

Constructors

Constructor and Description
SnowflakeShardingKeyGenerator()

Method Summary

Modifier and Type	Method and Description
Comparable<?>	generateKey()
String	getType()

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface org.apache.shardingsphere.spi.TypeBasedSPI

getProperties, setProperties

Field Detail

EPOCH

public static final long EPOCH

Constructor Detail

SnowflakeShardingKeyGenerator

public SnowflakeShardingKeyGenerator()

Method Detail

getType

public String getType()

Specified by:

getType in interface TypeBasedSPI

generateKey

public Comparable<?> generateKey()

Specified by:

generateKey in interface ShardingKeyGenerator