default long checksum(final Collection<? extends Checksum> factors, long v) {
        if (factors != null && !factors.isEmpty()) {
            for (final Checksum factor : factors) {
                v = checksum(v, factor.checksum());
            }
        }
        return v;
    }
Returns the checksum value of act on factors.

@param factors checksum collection
@param v origin checksum
@return checksum value
jraft-core/src/main/java/com/alipay/sofa/jraft/entity/Checksum.java