com.taobao.metamorphosis.client.consumer
枚举 HashAlgorithm

java.lang.Object
  java.lang.Enum<HashAlgorithm>
      com.taobao.metamorphosis.client.consumer.HashAlgorithm

所有已实现的接口：

Serializable, Comparable<HashAlgorithm>

public enum HashAlgorithm
extends Enum<HashAlgorithm>

Known hashing algorithms for locating a server for a key. Note that all hash algorithms return 64-bits of hash, but only the lower 32-bits are significant. This allows a positive 32-bit number to be returned for all cases.

枚举常量摘要

CRC32_HASH
CRC32_HASH as used by the perl API.

ELECTION_HASH

ELF_HASH

FNV1_32_HASH
32-bit FNV1.

FNV1_64_HASH
FNV hashes are designed to be fast while maintaining a low collision rate.

FNV1A_32_HASH
32-bit FNV1a.

FNV1A_64_HASH
Variation of FNV.

KETAMA_HASH
MD5-based hash algorithm used by ketama.

LUA_HASH
From lua source,it is used for long key

MYSQL_HASH
From mysql source

NATIVE_HASH
Native hash (String.hashCode()).

ONE_AT_A_TIME
The Jenkins One-at-a-time hash ,please see http://www.burtleburtle.net/bob/hash/doobs.html

RS_HASH

方法摘要

static byte[]	computeMd5(String k) Get the md5 of the given key.
long	hash(String k) Compute the hash for the given key.
static HashAlgorithm	valueOf(String name) 返回带有指定名称的该类型的枚举常量。
static HashAlgorithm[]	values() 按照声明该枚举类型的常量的顺序，返回 包含这些常量的数组。

从类 java.lang.Enum 继承的方法

clone, compareTo, equals, finalize, getDeclaringClass, hashCode, name, ordinal, toString, valueOf

从类 java.lang.Object 继承的方法

getClass, notify, notifyAll, wait, wait, wait

枚举常量详细信息

NATIVE_HASH

public static final HashAlgorithm NATIVE_HASH

Native hash (String.hashCode()).

CRC32_HASH

public static final HashAlgorithm CRC32_HASH

CRC32_HASH as used by the perl API. This will be more consistent both across multiple API users as well as java versions, but is mostly likely significantly slower.

FNV1_64_HASH

public static final HashAlgorithm FNV1_64_HASH

FNV hashes are designed to be fast while maintaining a low collision rate. The FNV speed allows one to quickly hash lots of data while maintaining a reasonable collision rate.

另请参见：

http://www.isthe.com/chongo/tech/comp/fnv/, http://en.wikipedia.org/wiki/Fowler_Noll_Vo_hash

FNV1A_64_HASH

public static final HashAlgorithm FNV1A_64_HASH

Variation of FNV.

FNV1_32_HASH

public static final HashAlgorithm FNV1_32_HASH

32-bit FNV1.

FNV1A_32_HASH

public static final HashAlgorithm FNV1A_32_HASH

32-bit FNV1a.

KETAMA_HASH

public static final HashAlgorithm KETAMA_HASH

MD5-based hash algorithm used by ketama.

MYSQL_HASH

public static final HashAlgorithm MYSQL_HASH

From mysql source

ELF_HASH

public static final HashAlgorithm ELF_HASH

RS_HASH

public static final HashAlgorithm RS_HASH

LUA_HASH

public static final HashAlgorithm LUA_HASH

From lua source,it is used for long key

ELECTION_HASH

public static final HashAlgorithm ELECTION_HASH

ONE_AT_A_TIME

public static final HashAlgorithm ONE_AT_A_TIME

The Jenkins One-at-a-time hash ,please see http://www.burtleburtle.net/bob/hash/doobs.html

方法详细信息

values

public static HashAlgorithm[] values()

按照声明该枚举类型的常量的顺序，返回 包含这些常量的数组。该方法可用于迭代 常量，如下所示：

for (HashAlgorithm c : HashAlgorithm.values())
    System.out.println(c);

valueOf

public static HashAlgorithm valueOf(String name)

返回带有指定名称的该类型的枚举常量。 字符串必须与用于声明该类型的枚举常量的 标识符完全匹配。（不允许有多余 的空格。）

参数：

name - 要返回的枚举常量的名称。

返回：

返回带有指定名称的枚举常量

抛出：

如果该枚举类型没有带有指定名称的常量， - 则抛出 IllegalArgumentException

hash

public long hash(String k)

Compute the hash for the given key.

返回：

a positive integer hash

computeMd5

public static byte[] computeMd5(String k)

Get the md5 of the given key.