cn.ujava.common.codec.hash

Class CityHash

java.lang.Object

cn.ujava.common.codec.hash.CityHash

All Implemented Interfaces:

Encoder<byte[],Number>, Hash128<byte[]>, Hash32<byte[]>, Hash64<byte[]>

public class CityHash
extends Object
implements Hash32<byte[]>, Hash64<byte[]>, Hash128<byte[]>

Google发布的Hash计算算法：CityHash64 与 CityHash128。
它们分别根据字串计算 64 和 128 位的散列值。这些算法不适用于加密，但适合用在散列表等处。

代码来自：https://github.com/rolandhe/string-tools
原始算法：https://github.com/google/cityhash

Author:

hexiufeng

Since:

5.2.5

Field Summary

Fields

Modifier and Type	Field and Description
static CityHash	INSTANCE 单例

Constructor Summary

Constructors

Constructor and Description
CityHash()

Method Summary

Modifier and Type	Method and Description
Number	encode(byte[] bytes) 执行编码
Number128	hash128(byte[] data) 计算128位City Hash值
Number128	hash128(byte[] data, Number128 seed) 计算128位City Hash值
int	hash32(byte[] data) 计算32位City Hash值
long	hash64(byte[] data) 计算64位City Hash值
long	hash64(byte[] data, long seed) 计算64位City Hash值，种子1使用默认的k2
long	hash64(byte[] data, long seed0, long seed1) 计算64位City Hash值

Methods inherited from class java.lang.Object

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

Field Detail

INSTANCE

public static CityHash INSTANCE

单例

Constructor Detail

CityHash

public CityHash()

Method Detail

encode

public Number encode(byte[] bytes)

Description copied from interface: Encoder

执行编码

Specified by:

encode in interface Encoder<byte[],Number>

Specified by:

encode in interface Hash128<byte[]>

Specified by:

encode in interface Hash32<byte[]>

Specified by:

encode in interface Hash64<byte[]>

Parameters:

bytes - 被编码的数据

Returns:

编码后的数据

hash32

public int hash32(byte[] data)

计算32位City Hash值

Specified by:

hash32 in interface Hash32<byte[]>

Parameters:

data - 数据

Returns:

hash值

hash64

public long hash64(byte[] data)

计算64位City Hash值

Specified by:

hash64 in interface Hash64<byte[]>

Parameters:

data - 数据

Returns:

hash值

hash64

public long hash64(byte[] data,
                   long seed0,
                   long seed1)

计算64位City Hash值

Parameters:

data - 数据

seed0 - 种子1

seed1 - 种子2

Returns:

hash值

hash64

public long hash64(byte[] data,
                   long seed)

计算64位City Hash值，种子1使用默认的k2

Parameters:

data - 数据

seed - 种子2

Returns:

hash值

hash128

public Number128 hash128(byte[] data)

计算128位City Hash值

Specified by:

hash128 in interface Hash128<byte[]>

Parameters:

data - 数据

Returns:

hash值

hash128

public Number128 hash128(byte[] data,
                         Number128 seed)

计算128位City Hash值

Parameters:

data - 数据

seed - 种子

Returns:

hash值