public static long hash64(int data) {
        long k1 = Integer.reverseBytes(data) & (-1L >>> 32);
        int length = Integer.BYTES;
        long hash = DEFAULT_SEED;
        k1 *= C1;
        k1 = Long.rotateLeft(k1, R1);
        k1 *= C2;
        hash ^= k1;
        // finalization
        hash ^= length;
        hash = fmix64(hash);
        return hash;
    }
Murmur3 64-bit variant. This is essentially MSB 8 bytes of Murmur3 128-bit variant.

@param data - input byte array
@return - hashcode
streams/src/main/java/org/apache/kafka/streams/state/internals/Murmur3.java