Mega Code Archive
FNV Hash
<![CDATA[
/*
* @(#)$Id$
*
* Copyright 2006-2008 Makoto YUI
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*
* Contributors:
* Makoto YUI - initial implementation
*/
//package xbird.util.hashes;
/**
*
* <DIV lang="en"></DIV>
* <DIV lang="ja"></DIV>
*
* @author Makoto YUI (yuin405+xbird@gmail.com)
* @link http://www.isthe.com/chongo/tech/comp/fnv/index.html
*/
public final class FNVHash {
private static final long FNV_64_INIT = 0xcbf29ce484222325L;
private static final long FNV_64_PRIME = 0x100000001b3L;
private static final int FNV_32_INIT = 0x811c9dc5;
private static final int FNV_32_PRIME = 0x01000193;
public FNVHash() {}
public static int hash32(final byte[] k) {
int rv = FNV_32_INIT;
final int len = k.length;
for(int i = 0; i < len; i++) {
rv ^= k[i];
rv *= FNV_32_PRIME;
}
return rv;
}
public static long hash64(final byte[] k) {
long rv = FNV_64_INIT;
final int len = k.length;
for(int i = 0; i < len; i++) {
rv ^= k[i];
rv *= FNV_64_PRIME;
}
return rv;
}
public static int hash32(final String k) {
int rv = FNV_32_INIT;
final int len = k.length();
for(int i = 0; i < len; i++) {
rv ^= k.charAt(i);
rv *= FNV_32_PRIME;
}
return rv;
}
public static long hash64(final String k) {
long rv = FNV_64_INIT;
final int len = k.length();
for(int i = 0; i < len; i++) {
rv ^= k.charAt(i);
rv *= FNV_64_PRIME;
}
return rv;
}
}
]]>