Murmur hash 3.0

MurmurHash

package rocks.ninjachen;

/**
 * Murmur hash 3.0.
 * <p>
 * It works as the same as lastguest\Murmur in PHP in limited test data.
 */
public final class MurmurHash {
    /**
     * @param key Text to hash.
     * @param seed   Positive integer only
     * @return number 32-bit positive integer hash(No unsigned-int in Java, use Long)
     */
    public static long hash3Int(String key, int seed) {
        byte[] bytes = key.getBytes();
        int klen = bytes.length;
        long h1 = seed < 0 ? -seed : seed; // positive seed
        int remainder = 0, i = 0;
        long k1;
        for (int mlen = klen - (remainder = klen & 3); i < mlen; ) {
            k1 = bytes[i]
                    | (bytes[++i] << 8)
                    | (bytes[++i] << 16)
                    | (bytes[++i] << 24);
            ++i;
            k1 = ((((k1 & 0xffffL) * 0xcc9e2d51) + (((((k1 >= 0 ? k1 >> 16 : ((k1 & 0x7fffffffL) >> 16) | 0x8000)) * 0xcc9e2d51) & 0xffffL) << 16))) & 0xffffffffL;
            k1 = k1 << 15 | (k1 >= 0 ? k1 >> 17 : ((k1 & 0x7fffffffL) >> 17) | 0x4000);
            k1 = ((((k1 & 0xffffL) * 0x1b873593) + (((((k1 >= 0 ? k1 >> 16 : ((k1 & 0x7fffffffL) >> 16) | 0x8000)) * 0x1b873593) & 0xffffL) << 16))) & 0xffffffffL;
            h1 ^= k1;
            h1 = h1 << 13 | (h1 >= 0 ? h1 >> 19 : ((h1 & 0x7fffffffL) >> 19) | 0x1000);
            long h1b = ((((h1 & 0xffffL) * 5) + (((((h1 >= 0 ? h1 >> 16 : ((h1 & 0x7fffffffL) >> 16) | 0x8000)) * 5) & 0xffffL) << 16))) & 0xffffffffL;
            h1 = (((h1b & 0xffffL) + 0x6b64) + (((((h1b >= 0 ? h1b >> 16 : ((h1b & 0x7fffffffL) >> 16) | 0x8000)) + 0xe654) & 0xffffL) << 16));
        }
        k1 = 0;
        switch (remainder) {
            case 3:
                k1 ^= bytes[i + 2] << 16;
            case 2:
                k1 ^= bytes[i + 1] << 8;
            case 1:
                k1 ^= bytes[i];
                k1 = (((k1 & 0xffffL) * 0xcc9e2d51) + (((((k1 >= 0 ? k1 >> 16 : ((k1 & 0x7fffffffL) >> 16) | 0x8000)) * 0xcc9e2d51) & 0xffffL) << 16)) & 0xffffffffL;
                k1 = k1 << 15 | (k1 >= 0 ? k1 >> 17 : ((k1 & 0x7fffffffL) >> 17) | 0x4000);
                k1 = (((k1 & 0xffffL) * 0x1b873593) + (((((k1 >= 0 ? k1 >> 16 : ((k1 & 0x7fffffffL) >> 16) | 0x8000)) * 0x1b873593) & 0xffffL) << 16)) & 0xffffffffL;
                h1 ^= k1;
        }
        h1 ^= klen;
        h1 ^= (h1 >= 0 ? h1 >> 16 : ((h1 & 0x7fffffffL) >> 16) | 0x8000);
        h1 = (((h1 & 0xffffL) * 0x85ebca6b) + (((((h1 >= 0 ? h1 >> 16 : ((h1 & 0x7fffffffL) >> 16) | 0x8000)) * 0x85ebca6b) & 0xffffL) << 16)) & 0xffffffffL;
        h1 ^= (h1 >= 0 ? h1 >> 13 : ((h1 & 0x7fffffffL) >> 13) | 0x40000);
        h1 = ((((h1 & 0xffffL) * 0xc2b2ae35) + (((((h1 >= 0 ? h1 >> 16 : ((h1 & 0x7fffffffL) >> 16) | 0x8000)) * 0xc2b2ae35) & 0xffffL) << 16))) & 0xffffffffL;
        h1 ^= (h1 >= 0 ? h1 >> 16 : ((h1 & 0x7fffffffL) >> 16) | 0x8000);
        return h1;
    }

    public static long hash3IntModulo(String key, int divisor, int seed) {
        return hash3Int(key, seed) % divisor;
    }
}