Adding BigDecimal.ZERO to another BigDecimal value

Question

I am still learning Java, and I read articles on several sites. I found an article in Java Code Geeks that I have a question about. The article explains the principle of opening / closing. The article uses the scenario of applying discounts to the company's product for an example. The first part of the code is as follows:

import java.math.BigDecimal;
import java.math.RoundingMode;

public class Discount {

    public BigDecimal apply(BigDecimal price) {

        BigDecimal percent = new BigDecimal("0.10");
        BigDecimal discount = price.multiply(percent);
        return price.subtract(discount.setScale(2, RoundingMode.HALF_UP));
    }
}

The second part of the code is as follows:

import java.math.BigDecimal;

public class DiscountService {

    public BigDecimal applyDiscounts(BigDecimal price,Discount discount) {

        BigDecimal discountPrice = price.add(BigDecimal.ZERO);
        discountPrice = discount.apply(discountPrice);
        return discountPrice;
   }
}

The Oracle site says that ZERO in BigDecimal has a value of 0 and a scale of zero. Does this mean that in price.add(BigDecimal.ZERO)we just add 0 to the price that brought? If so, why? Or is it just that you need to abandon decimal places? Or is there some other purpose?

Thanks!

Answer 1

price.add(BigDecimal.ZERO) BigDecimal, BigDecimal .

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