docs: public static BigDecimal div(BigDecimal v1, BigDecimal v2, int scale, RoundingMode roundingMode) {
  		Assert.notNull(v2, "Divisor must be not null !");
  		if (null == v1) {
  			return BigDecimal.ZERO;
  		}
  		if (scale < 0) {
  			scale = -scale;
  		}
  		return v1.divide(v2, scale, roundingMode);
  	}