Java Murmur Hash murmurHash3(int x)

Description

Avalanches the bits of an integer by applying the finalisation step of MurmurHash3.

License

Apache License

Parameter

Parameter	Description
x	an integer.

Return

a hash value with good avalanching properties.

Declaration

public final static int murmurHash3(int x) 

Method Source Code

//package com.java2s;
/*       /*from ww  w  .  j a  v  a  2  s .  c  o m*/
 * Copyright (C) 2002-2015 Sebastiano Vigna
 *
 * 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. 
 */

public class Main {
    /** Avalanches the bits of an integer by applying the finalisation step of MurmurHash3.
     * 
     * <p>This method implements the finalisation step of Austin Appleby's <a href="http://code.google.com/p/smhasher/">MurmurHash3</a>.
     * Its purpose is to avalanche the bits of the argument to within 0.25% bias.
     * 
     * @param x an integer.
     * @return a hash value with good avalanching properties.
     */
    public final static int murmurHash3(int x) {
        x ^= x >>> 16;
        x *= 0x85ebca6b;
        x ^= x >>> 13;
        x *= 0xc2b2ae35;
        x ^= x >>> 16;
        return x;
    }

    /** Avalanches the bits of a long integer by applying the finalisation step of MurmurHash3.
     * 
     * <p>This method implements the finalisation step of Austin Appleby's <a href="http://code.google.com/p/smhasher/">MurmurHash3</a>.
     * Its purpose is to avalanche the bits of the argument to within 0.25% bias.
     * 
     * @param x a long integer.
     * @return a hash value with good avalanching properties.
     */
    public final static long murmurHash3(long x) {
        x ^= x >>> 33;
        x *= 0xff51afd7ed558ccdL;
        x ^= x >>> 33;
        x *= 0xc4ceb9fe1a85ec53L;
        x ^= x >>> 33;
        return x;
    }
}

Related

1. murmur3fmix(int value)
2. murmurHash(byte[] data, int offset, int length)
3. murmurHash(int code)
4. murmurhash2_64(final byte[] data, int length, int seed)
5. murmurHash3(int k)
6. murmurHash3(int x)
7. MurmurHash3_fmix(int k)
8. murmurhash3x8632(byte[] data, int offset, int len, int seed)
9. murmurMix(long h)