@Override
    public int compareTo(Bytes that) {
        return BytesUtil.getDefaultByteArrayComparator().compare(this.bytes, that.bytes);
    }
The hashcode is cached except for the case where it is computed as 0, in which
case we compute the hashcode on every call.

@return the hashcode
jraft-core/src/main/java/com/alipay/sofa/jraft/util/Bytes.java