转贴--Java Hash算法大全
/**
* Hash算法大全<br>
* 推荐使用FNV1算法
* @algorithm None
* @author Goodzzp 2006-11-20
* @lastEdit Goodzzp 2006-11-20
* @editDetail Create
*/
public class HashAlgorithms
{
/** //**
* 加法hash
* @param key 字符串
* @param prime 一个质数
* @return hash结果
*/
public static int additiveHash(String key, int prime)
{
int hash, i;
for (hash = key.length(), i = 0 ; i < key.length(); i ++ )
hash += key.charAt(i);
return (hash % prime);
}
/** //**
* 旋转hash
* @param key 输入字符串
* @param prime 质数
* @return hash值
*/
public static int rotatingHash(String key, int prime)
{
int hash, i;
for (hash = key.length(), i = 0 ; i < key.length(); ++ i)
hash = (hash << 4 ) ^ (hash >> 28 ) ^ key.charAt(i);
return (hash % prime);
// return (hash ^ (hash>>10) ^ (hash>>20));
}
// 替代：
// 使用：hash = (hash ^ (hash>>10) ^ (hash>>20)) & mask;
// 替代：hash %= prime;
/** //**
* MASK值，随便找一个值，最好是质数
*/
static int M_MASK = 0x8765fed1 ;
/** //**
* 一次一个hash
* @param key 输入字符串
* @return 输出hash值
*/
public static int oneByOneHash(String key)
{
int hash, i;
for (hash = 0 , i = 0 ; i < key.length(); ++ i)
{
hash += key.charAt(i);
hash += (hash << 10 );
hash ^= (hash >> 6 );
}
hash += (hash << 3 );
hash ^= (hash >> 11 );
hash += (hash << 15 );
// return (hash & M_MASK);
return hash;
}
/** //**
* Bernstein's hash
* @param key 输入字节数组
* @param level 初始hash常量
* @return 结果hash
*/
public static int bernstein(String key)
{
int hash = 0 ;
int i;
for (i = 0 ; i < key.length(); ++ i) hash = 33 * hash + key.charAt(i);
return hash;
}
//
/** ///// Pearson's Hash
// char pearson(char[]key, ub4 len, char tab[256])
// {
// char hash;
// ub4 i;
// for (hash=len, i=0; i<len; ++i)
// hash=tab[hash^key[i]];
// return (hash);
// }
/* *///// CRC Hashing，计算crc,具体代码见其他
// ub4 crc(char *key, ub4 len, ub4 mask, ub4 tab[256])
// {
// ub4 hash, i;
// for (hash=len, i=0; i<len; ++i)
// hash = (hash >> 8) ^ tab[(hash & 0xff) ^ key[i]];
// return (hash & mask);
// }
/** //**
* Universal Hashing
*/
public static int universal( char []key, int mask, int [] tab)
{
int hash = key.length, i, len = key.length;
for (i = 0 ; i < (len << 3 ); i += 8 )
{
char k = key[i >> 3 ];
if ((k & 0x01 ) == 0 ) hash ^= tab[i + 0 ];
if ((k & 0x02 ) == 0 ) hash ^= tab[i + 1 ];
if ((k & 0x04 ) == 0 ) hash ^= tab[i + 2 ];
if ((k & 0x08 ) == 0 ) hash ^= tab[i + 3 ];
if ((k & 0x10 ) == 0 ) hash ^= tab[i + 4 ];
if ((k & 0x20 ) == 0 ) hash ^= tab[i + 5 ];
if ((k & 0x40 ) == 0 ) hash ^= tab[i + 6 ];
if ((k & 0x80 ) == 0 ) hash ^= tab[i + 7 ];
}
return (hash & mask);
}
/** //**
* Zobrist Hashing
*/
public static int zobrist( char [] key, int mask, int [][] tab)
{
int hash, i;
for (hash = key.length, i = 0 ; i < key.length; ++ i)
hash ^= tab[i][key[i]];
return (hash & mask);
}
// LOOKUP3
// 见Bob Jenkins(3).c文件
// 32位FNV算法
static int M_SHIFT = 0 ;
/** //**
* 32位的FNV算法
* @param data 数组
* @return int值
*/
public static int FNVHash( byte [] data)
{
int hash = ( int ) 2166136261L ;
for ( byte b : data)
hash = (hash * 16777619 ) ^ b;
if (M_SHIFT == 0 )
return hash;
return (hash ^ (hash >> M_SHIFT)) & M_MASK;
}
/** //**
* 改进的32位FNV算法1
* @param data 数组
* @return int值
*/
public static int FNVHash1( byte [] data)
{
final int p = 16777619 ;
int hash = ( int ) 2166136261L ;
for ( byte b:data)
hash = (hash ^ b) * p;
hash += hash << 13 ;
hash ^= hash >> 7 ;
hash += hash << 3 ;
hash ^= hash >> 17 ;
hash += hash << 5 ;
return hash;
}
/** //**
* 改进的32位FNV算法1
* @param data 字符串
* @return int值
*/
public static int FNVHash1(String data)
{
final int p = 16777619 ;
int hash = ( int ) 2166136261L ;
for ( int i = 0 ;i < data.length();i ++ )
hash = (hash ^ data.charAt(i)) * p;
hash += hash << 13 ;
hash ^= hash >> 7 ;
hash += hash << 3 ;
hash ^= hash >> 17 ;
hash += hash << 5 ;
return hash;
}
/** //**
* Thomas Wang的算法，整数hash
*/
public static int intHash( int key)
{
key += ~ (key << 15 );
key ^= (key >>> 10 );
key += (key << 3 );
key ^= (key >>> 6 );
key += ~ (key << 11 );
key ^= (key >>> 16 );
return key;
}
/** //**
* RS算法hash
* @param str 字符串
*/
public static int RSHash(String str)
{
int b = 378551 ;
int a = 63689 ;
int hash = 0 ;
for ( int i = 0 ; i < str.length(); i ++ )
{
hash = hash * a + str.charAt(i);
a = a * b;
}
return (hash & 0x7FFFFFFF );
}
/** //* End Of RS Hash Function */
/** //**
* JS算法
*/
public static int JSHash(String str)
{
int hash = 1315423911 ;
for ( int i = 0 ; i < str.length(); i ++ )
{
hash ^= ((hash << 5 ) + str.charAt(i) + (hash >> 2 ));
}
return (hash & 0x7FFFFFFF );
}
/** //* End Of JS Hash Function */
/** //**
* PJW算法
*/
public static int PJWHash(String str)
{
int BitsInUnsignedInt = 32 ;
int ThreeQuarters = (BitsInUnsignedInt * 3 ) / 4 ;
int OneEighth = BitsInUnsignedInt / 8 ;
int HighBits = 0xFFFFFFFF << (BitsInUnsignedInt - OneEighth);
int hash = 0 ;
int test = 0 ;
for ( int i = 0 ; i < str.length();i ++ )
{
hash = (hash << OneEighth) + str.charAt(i);
if ((test = hash & HighBits) != 0 )
{
hash = (( hash ^ (test >> ThreeQuarters)) & ( ~ HighBits));
}
}
return (hash & 0x7FFFFFFF );
}
/** //* End Of P. J. Weinberger Hash Function */
/** //**
* ELF算法
*/
public static int ELFHash(String str)
{
int hash = 0 ;
int x = 0 ;
for ( int i = 0 ; i < str.length(); i ++ )
{
hash = (hash << 4 ) + str.charAt(i);
if ((x = ( int )(hash & 0xF0000000L )) != 0 )
{
hash ^= (x >> 24 );
hash &= ~ x;
}
}
return (hash & 0x7FFFFFFF );
}
/** //* End Of ELF Hash Function */
/** //**
* BKDR算法
*/
public static int BKDRHash(String str)
{
int seed = 131 ; // 31 131 1313 13131 131313 etc..
int hash = 0 ;
for ( int i = 0 ; i < str.length(); i ++ )
{
hash = (hash * seed) + str.charAt(i);
}
return (hash & 0x7FFFFFFF );
}
/** //* End Of BKDR Hash Function */
/** //**
* SDBM算法
*/
public static int SDBMHash(String str)
{
int hash = 0 ;
for ( int i = 0 ; i < str.length(); i ++ )
{
hash = str.charAt(i) + (hash << 6 ) + (hash << 16 ) - hash;
}
return (hash & 0x7FFFFFFF );
}
/** //* End Of SDBM Hash Function */
/** //**
* DJB算法
*/
public static int DJBHash(String str)
{
int hash = 5381 ;
for ( int i = 0 ; i < str.length(); i ++ )
{
hash = ((hash << 5 ) + hash) + str.charAt(i);
}
return (hash & 0x7FFFFFFF );
}
/** //* End Of DJB Hash Function */
/** //**
* DEK算法
*/
public static int DEKHash(String str)
{
int hash = str.length();
for ( int i = 0 ; i < str.length(); i ++ )
{
hash = ((hash << 5 ) ^ (hash >> 27 )) ^ str.charAt(i);
}
return (hash & 0x7FFFFFFF );
}
/** //* End Of DEK Hash Function */
/** //**
* AP算法
*/
public static int APHash(String str)
{
int hash = 0 ;
for ( int i = 0 ; i < str.length(); i ++ )
{
hash ^= ((i & 1 ) == 0 ) ? ( (hash << 7 ) ^ str.charAt(i) ^ (hash >> 3 )) :
( ~ ((hash << 11 ) ^ str.charAt(i) ^ (hash >> 5 )));
}
// return (hash & 0x7FFFFFFF);
return hash;
}
/** //* End Of AP Hash Function */
/** //**
* JAVA自己带的算法
*/
public static int java(String str)
{
int h = 0 ;
int off = 0 ;
int len = str.length();
for ( int i = 0 ; i < len; i ++ )
{
h = 31 * h + str.charAt(off ++ );
}
return h;
}
/** //**
* 混合hash算法，输出64位的值
*/
public static long mixHash(String str)
{
long hash = str.hashCode();
hash <<= 32 ;
hash |= FNVHash1(str);
return hash;
}
}
* Hash算法大全<br>
* 推荐使用FNV1算法
* @algorithm None
* @author Goodzzp 2006-11-20
* @lastEdit Goodzzp 2006-11-20
* @editDetail Create
*/
public class HashAlgorithms
{
/** //**
* 加法hash
* @param key 字符串
* @param prime 一个质数
* @return hash结果
*/
public static int additiveHash(String key, int prime)
{
int hash, i;
for (hash = key.length(), i = 0 ; i < key.length(); i ++ )
hash += key.charAt(i);
return (hash % prime);
}
/** //**
* 旋转hash
* @param key 输入字符串
* @param prime 质数
* @return hash值
*/
public static int rotatingHash(String key, int prime)
{
int hash, i;
for (hash = key.length(), i = 0 ; i < key.length(); ++ i)
hash = (hash << 4 ) ^ (hash >> 28 ) ^ key.charAt(i);
return (hash % prime);
// return (hash ^ (hash>>10) ^ (hash>>20));
}
// 替代：
// 使用：hash = (hash ^ (hash>>10) ^ (hash>>20)) & mask;
// 替代：hash %= prime;
/** //**
* MASK值，随便找一个值，最好是质数
*/
static int M_MASK = 0x8765fed1 ;
/** //**
* 一次一个hash
* @param key 输入字符串
* @return 输出hash值
*/
public static int oneByOneHash(String key)
{
int hash, i;
for (hash = 0 , i = 0 ; i < key.length(); ++ i)
{
hash += key.charAt(i);
hash += (hash << 10 );
hash ^= (hash >> 6 );
}
hash += (hash << 3 );
hash ^= (hash >> 11 );
hash += (hash << 15 );
// return (hash & M_MASK);
return hash;
}
/** //**
* Bernstein's hash
* @param key 输入字节数组
* @param level 初始hash常量
* @return 结果hash
*/
public static int bernstein(String key)
{
int hash = 0 ;
int i;
for (i = 0 ; i < key.length(); ++ i) hash = 33 * hash + key.charAt(i);
return hash;
}
//
/** ///// Pearson's Hash
// char pearson(char[]key, ub4 len, char tab[256])
// {
// char hash;
// ub4 i;
// for (hash=len, i=0; i<len; ++i)
// hash=tab[hash^key[i]];
// return (hash);
// }
/* *///// CRC Hashing，计算crc,具体代码见其他
// ub4 crc(char *key, ub4 len, ub4 mask, ub4 tab[256])
// {
// ub4 hash, i;
// for (hash=len, i=0; i<len; ++i)
// hash = (hash >> 8) ^ tab[(hash & 0xff) ^ key[i]];
// return (hash & mask);
// }
/** //**
* Universal Hashing
*/
public static int universal( char []key, int mask, int [] tab)
{
int hash = key.length, i, len = key.length;
for (i = 0 ; i < (len << 3 ); i += 8 )
{
char k = key[i >> 3 ];
if ((k & 0x01 ) == 0 ) hash ^= tab[i + 0 ];
if ((k & 0x02 ) == 0 ) hash ^= tab[i + 1 ];
if ((k & 0x04 ) == 0 ) hash ^= tab[i + 2 ];
if ((k & 0x08 ) == 0 ) hash ^= tab[i + 3 ];
if ((k & 0x10 ) == 0 ) hash ^= tab[i + 4 ];
if ((k & 0x20 ) == 0 ) hash ^= tab[i + 5 ];
if ((k & 0x40 ) == 0 ) hash ^= tab[i + 6 ];
if ((k & 0x80 ) == 0 ) hash ^= tab[i + 7 ];
}
return (hash & mask);
}
/** //**
* Zobrist Hashing
*/
public static int zobrist( char [] key, int mask, int [][] tab)
{
int hash, i;
for (hash = key.length, i = 0 ; i < key.length; ++ i)
hash ^= tab[i][key[i]];
return (hash & mask);
}
// LOOKUP3
// 见Bob Jenkins(3).c文件
// 32位FNV算法
static int M_SHIFT = 0 ;
/** //**
* 32位的FNV算法
* @param data 数组
* @return int值
*/
public static int FNVHash( byte [] data)
{
int hash = ( int ) 2166136261L ;
for ( byte b : data)
hash = (hash * 16777619 ) ^ b;
if (M_SHIFT == 0 )
return hash;
return (hash ^ (hash >> M_SHIFT)) & M_MASK;
}
/** //**
* 改进的32位FNV算法1
* @param data 数组
* @return int值
*/
public static int FNVHash1( byte [] data)
{
final int p = 16777619 ;
int hash = ( int ) 2166136261L ;
for ( byte b:data)
hash = (hash ^ b) * p;
hash += hash << 13 ;
hash ^= hash >> 7 ;
hash += hash << 3 ;
hash ^= hash >> 17 ;
hash += hash << 5 ;
return hash;
}
/** //**
* 改进的32位FNV算法1
* @param data 字符串
* @return int值
*/
public static int FNVHash1(String data)
{
final int p = 16777619 ;
int hash = ( int ) 2166136261L ;
for ( int i = 0 ;i < data.length();i ++ )
hash = (hash ^ data.charAt(i)) * p;
hash += hash << 13 ;
hash ^= hash >> 7 ;
hash += hash << 3 ;
hash ^= hash >> 17 ;
hash += hash << 5 ;
return hash;
}
/** //**
* Thomas Wang的算法，整数hash
*/
public static int intHash( int key)
{
key += ~ (key << 15 );
key ^= (key >>> 10 );
key += (key << 3 );
key ^= (key >>> 6 );
key += ~ (key << 11 );
key ^= (key >>> 16 );
return key;
}
/** //**
* RS算法hash
* @param str 字符串
*/
public static int RSHash(String str)
{
int b = 378551 ;
int a = 63689 ;
int hash = 0 ;
for ( int i = 0 ; i < str.length(); i ++ )
{
hash = hash * a + str.charAt(i);
a = a * b;
}
return (hash & 0x7FFFFFFF );
}
/** //* End Of RS Hash Function */
/** //**
* JS算法
*/
public static int JSHash(String str)
{
int hash = 1315423911 ;
for ( int i = 0 ; i < str.length(); i ++ )
{
hash ^= ((hash << 5 ) + str.charAt(i) + (hash >> 2 ));
}
return (hash & 0x7FFFFFFF );
}
/** //* End Of JS Hash Function */
/** //**
* PJW算法
*/
public static int PJWHash(String str)
{
int BitsInUnsignedInt = 32 ;
int ThreeQuarters = (BitsInUnsignedInt * 3 ) / 4 ;
int OneEighth = BitsInUnsignedInt / 8 ;
int HighBits = 0xFFFFFFFF << (BitsInUnsignedInt - OneEighth);
int hash = 0 ;
int test = 0 ;
for ( int i = 0 ; i < str.length();i ++ )
{
hash = (hash << OneEighth) + str.charAt(i);
if ((test = hash & HighBits) != 0 )
{
hash = (( hash ^ (test >> ThreeQuarters)) & ( ~ HighBits));
}
}
return (hash & 0x7FFFFFFF );
}
/** //* End Of P. J. Weinberger Hash Function */
/** //**
* ELF算法
*/
public static int ELFHash(String str)
{
int hash = 0 ;
int x = 0 ;
for ( int i = 0 ; i < str.length(); i ++ )
{
hash = (hash << 4 ) + str.charAt(i);
if ((x = ( int )(hash & 0xF0000000L )) != 0 )
{
hash ^= (x >> 24 );
hash &= ~ x;
}
}
return (hash & 0x7FFFFFFF );
}
/** //* End Of ELF Hash Function */
/** //**
* BKDR算法
*/
public static int BKDRHash(String str)
{
int seed = 131 ; // 31 131 1313 13131 131313 etc..
int hash = 0 ;
for ( int i = 0 ; i < str.length(); i ++ )
{
hash = (hash * seed) + str.charAt(i);
}
return (hash & 0x7FFFFFFF );
}
/** //* End Of BKDR Hash Function */
/** //**
* SDBM算法
*/
public static int SDBMHash(String str)
{
int hash = 0 ;
for ( int i = 0 ; i < str.length(); i ++ )
{
hash = str.charAt(i) + (hash << 6 ) + (hash << 16 ) - hash;
}
return (hash & 0x7FFFFFFF );
}
/** //* End Of SDBM Hash Function */
/** //**
* DJB算法
*/
public static int DJBHash(String str)
{
int hash = 5381 ;
for ( int i = 0 ; i < str.length(); i ++ )
{
hash = ((hash << 5 ) + hash) + str.charAt(i);
}
return (hash & 0x7FFFFFFF );
}
/** //* End Of DJB Hash Function */
/** //**
* DEK算法
*/
public static int DEKHash(String str)
{
int hash = str.length();
for ( int i = 0 ; i < str.length(); i ++ )
{
hash = ((hash << 5 ) ^ (hash >> 27 )) ^ str.charAt(i);
}
return (hash & 0x7FFFFFFF );
}
/** //* End Of DEK Hash Function */
/** //**
* AP算法
*/
public static int APHash(String str)
{
int hash = 0 ;
for ( int i = 0 ; i < str.length(); i ++ )
{
hash ^= ((i & 1 ) == 0 ) ? ( (hash << 7 ) ^ str.charAt(i) ^ (hash >> 3 )) :
( ~ ((hash << 11 ) ^ str.charAt(i) ^ (hash >> 5 )));
}
// return (hash & 0x7FFFFFFF);
return hash;
}
/** //* End Of AP Hash Function */
/** //**
* JAVA自己带的算法
*/
public static int java(String str)
{
int h = 0 ;
int off = 0 ;
int len = str.length();
for ( int i = 0 ; i < len; i ++ )
{
h = 31 * h + str.charAt(off ++ );
}
return h;
}
/** //**
* 混合hash算法，输出64位的值
*/
public static long mixHash(String str)
{
long hash = str.hashCode();
hash <<= 32 ;
hash |= FNVHash1(str);
return hash;
}
}