me.ahoo.cosid.shardingsphere.sharding.interval

Class AbstractIntervalShardingAlgorithm<T extends java.lang.Comparable<?>>

java.lang.Object

me.ahoo.cosid.shardingsphere.sharding.interval.AbstractIntervalShardingAlgorithm<T>

All Implemented Interfaces:

org.apache.shardingsphere.infra.config.algorithm.ShardingSphereAlgorithm, org.apache.shardingsphere.infra.util.spi.lifecycle.SPIPostProcessor, org.apache.shardingsphere.infra.util.spi.type.typed.TypedSPI, org.apache.shardingsphere.sharding.api.sharding.standard.StandardShardingAlgorithm<T>, org.apache.shardingsphere.sharding.spi.ShardingAlgorithm

Direct Known Subclasses:

CosIdIntervalShardingAlgorithm, CosIdSnowflakeIntervalShardingAlgorithm

public abstract class AbstractIntervalShardingAlgorithm<T extends java.lang.Comparable<?>>
extends java.lang.Object
implements org.apache.shardingsphere.sharding.api.sharding.standard.StandardShardingAlgorithm<T>

基于间隔的时间范围分片算法.

 1. 易用性 支持多种数据类型 (Long:时间戳、LocalDateTime、DATE)，而官方的实现是先转换成字符串再转换成 LocalDateTime，转换成功率受时间格式化字符影响
 2. 性能
 -- 2.1 算法复杂度:[O(1)]，而官方的实现使用的是遍历查找[O(N)] {org.apache.shardingsphere.sharding.algorithm.sharding.datetime.IntervalShardingAlgorithm}
 -- 2.2 降低解析与转换成本，而官方的实现使用的是先转换成字符串，然后再转换成 LocalDateTime
 

分配策略=[逻辑名] + [分片算法]，分片算法KEY在全局唯一，这种方式显然是不利于缓存优化的，即doSharding(Collection, RangeShardingValue)的第一个参数availableTargetNames应该在绑定时已知且稳定，作为实例变量更利于性能。

See Also:

CosIdIntervalShardingAlgorithm, CosIdSnowflakeIntervalShardingAlgorithm

Field Summary

Fields

Modifier and Type	Field and Description
static java.lang.String	DATE_TIME_LOWER_KEY
static java.lang.String	DATE_TIME_UPPER_KEY
static java.time.format.DateTimeFormatter	DEFAULT_DATE_TIME_FORMATTER
static java.lang.String	DEFAULT_DATE_TIME_PATTERN
static java.lang.String	INTERVAL_AMOUNT_KEY
static java.lang.String	INTERVAL_UNIT_KEY
static java.lang.String	SHARDING_SUFFIX_FORMAT_KEY
static java.lang.String	TYPE_PREFIX
static java.lang.String	ZONE_ID_KEY

Constructor Summary

Constructors

Constructor and Description
AbstractIntervalShardingAlgorithm()

Method Summary

Modifier and Type	Method and Description
protected com.google.common.collect.Range<java.time.LocalDateTime>	convertRangeShardingValue(com.google.common.collect.Range<T> shardingValue)
protected abstract java.time.LocalDateTime	convertShardingValue(T shardingValue) convert sharding value to LocalDateTime.
java.lang.String	doSharding(java.util.Collection<java.lang.String> availableTargetNames, org.apache.shardingsphere.sharding.api.sharding.standard.PreciseShardingValue<T> shardingValue)
java.util.Collection<java.lang.String>	doSharding(java.util.Collection<java.lang.String> availableTargetNames, org.apache.shardingsphere.sharding.api.sharding.standard.RangeShardingValue<T> shardingValue)
java.util.Properties	getProps()
protected java.lang.String	getRequiredValue(java.lang.String key)
me.ahoo.cosid.sharding.Sharding<java.time.LocalDateTime>	getSharding()
protected java.time.ZoneId	getZoneId()
void	init(java.util.Properties props)

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.infra.util.spi.type.typed.TypedSPI

getType, getTypeAliases

Field Detail

TYPE_PREFIX

public static final java.lang.String TYPE_PREFIX

See Also:

Constant Field Values

DEFAULT_DATE_TIME_PATTERN

public static final java.lang.String DEFAULT_DATE_TIME_PATTERN

See Also:

Constant Field Values

DEFAULT_DATE_TIME_FORMATTER

public static final java.time.format.DateTimeFormatter DEFAULT_DATE_TIME_FORMATTER

DATE_TIME_LOWER_KEY

public static final java.lang.String DATE_TIME_LOWER_KEY

See Also:

Constant Field Values

DATE_TIME_UPPER_KEY

public static final java.lang.String DATE_TIME_UPPER_KEY

See Also:

Constant Field Values

SHARDING_SUFFIX_FORMAT_KEY

public static final java.lang.String SHARDING_SUFFIX_FORMAT_KEY

See Also:

Constant Field Values

INTERVAL_UNIT_KEY

public static final java.lang.String INTERVAL_UNIT_KEY

See Also:

Constant Field Values

INTERVAL_AMOUNT_KEY

public static final java.lang.String INTERVAL_AMOUNT_KEY

See Also:

Constant Field Values

ZONE_ID_KEY

public static final java.lang.String ZONE_ID_KEY

See Also:

Constant Field Values

Constructor Detail

AbstractIntervalShardingAlgorithm

public AbstractIntervalShardingAlgorithm()

Method Detail

getProps

public java.util.Properties getProps()

Specified by:

getProps in interface org.apache.shardingsphere.infra.config.algorithm.ShardingSphereAlgorithm

getZoneId

protected java.time.ZoneId getZoneId()

init

public void init(java.util.Properties props)

Specified by:

init in interface org.apache.shardingsphere.infra.util.spi.lifecycle.SPIPostProcessor

getRequiredValue

protected java.lang.String getRequiredValue(java.lang.String key)

getSharding

public me.ahoo.cosid.sharding.Sharding<java.time.LocalDateTime> getSharding()

doSharding

public java.lang.String doSharding(java.util.Collection<java.lang.String> availableTargetNames,
                                   org.apache.shardingsphere.sharding.api.sharding.standard.PreciseShardingValue<T> shardingValue)

Specified by:

doSharding in interface org.apache.shardingsphere.sharding.api.sharding.standard.StandardShardingAlgorithm<T extends java.lang.Comparable<?>>

doSharding

public java.util.Collection<java.lang.String> doSharding(java.util.Collection<java.lang.String> availableTargetNames,
                                                         org.apache.shardingsphere.sharding.api.sharding.standard.RangeShardingValue<T> shardingValue)

Specified by:

doSharding in interface org.apache.shardingsphere.sharding.api.sharding.standard.StandardShardingAlgorithm<T extends java.lang.Comparable<?>>

convertShardingValue

protected abstract java.time.LocalDateTime convertShardingValue(T shardingValue)

convert sharding value to LocalDateTime.

Parameters:

shardingValue - sharding value

Returns:

The LocalDateTime represented by the sharding value

convertRangeShardingValue

protected com.google.common.collect.Range<java.time.LocalDateTime> convertRangeShardingValue(com.google.common.collect.Range<T> shardingValue)