PriceCalculatorImpl.java

package org.books.business;

import org.books.domain.Address;
import org.books.domain.LineItem;
import org.books.domain.PaymentInfo;

import javax.ejb.Stateless;
import java.util.List;

@Stateless
public class PriceCalculatorImpl implements PriceCalculator {

    public double getTotalPrice(List<LineItem> lineItems, Address address, PaymentInfo paymentInfo) {
        double totalPrice = 0;
        for (LineItem lineItem : lineItems) {
            totalPrice += lineItem.getQuantity() * lineItem.getBook().getPrice();
        }
        return totalPrice;
    }

}