public void validate(Object obj, Errors errors) {
        PriceIncrease pi = (PriceIncrease) obj;
        if (pi == null) {
            errors.rejectValue("percentage", "error.not-specified", null, "Value required.");
        }
        else {
            logger.info("Validating with " + pi + ": " + pi.getPercentage());
            if (pi.getPercentage() > maxPercentage) {
                errors.rejectValue("percentage", "error.too-high",
                    new Object[] {new Integer(maxPercentage)}, "Value too high.");
            }
            if (pi.getPercentage() <= minPercentage) {
                errors.rejectValue("percentage", "error.too-low",
                    new Object[] {new Integer(minPercentage)}, "Value too low.");
            }
        }
    }