Implementation adjustment

package lfet.demo;

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

public class InvoiceTotal implements InvoiceTotal_iFace<InvoiceTotal_model> {

    private final InvoiceTotal_rulesEngine rulesEngine = new InvoiceTotal_rulesEngine();

    public void computeInvoiceTotal(InvoiceTotal_model model) {

        model.setTotalDiscount(BigDecimal.ZERO);
        model.setTotalPostage(BigDecimal.ZERO);
        model.setTotalAmount(BigDecimal.ZERO);

        rulesEngine.execute(this, model);
    }

    /**
     * @param d any double value,
     *          NEGATIVE_INFINITY will be replaced Double.MAX_VALUE * -1.0,
     *          POSITIVE_INFINITY will be replaced Double.MAX_VALUE
     * @return the value as BigDecimal, scale 2, RoundingMode.HALF_UP
     */
    public BigDecimal bigDecimal(double d) {
        return new BigDecimal(Double.toString(
                d < Double.MAX_VALUE * -1.0 ? Double.MAX_VALUE * -1.0
                        : Math.min(d, Double.MAX_VALUE)))
                .setScale(2, RoundingMode.HALF_EVEN);
    }

    /**
     * <b>C01: Purchase order value</b><br>
     * <br>
     * The enum generation has been triggered in project.ini by:<br>
     * - <b>ide.java.interface.enum.1</b>: symbol=Interval; include.tags.title=purchase order; exclude.tags.title=discount
     */
    @Override
    public boolean isPurchaseOrderValue(InvoiceTotal_iFace.PurchaseOrderValue arg0, InvoiceTotal_model model) {
        return model.getOrderValue().compareTo(bigDecimal(arg0.getSymbolMin())) >= 0 &&
                model.getOrderValue().compareTo(bigDecimal(arg0.getSymbolMax())) <= 0;
    }

    /**
     * <b>C02: Discount</b><br>
     * <br>
     * <b>C02/01: &gt;0 - discount given</b>
     */
    public boolean isDiscount_Greater0(InvoiceTotal_model model) {
        return model.getOrderDiscount().compareTo(BigDecimal.ZERO) > 0;
    }

    /**
     * <b>C03: Discount type</b><br>
     * <br>
     * <b>C03/01: % - percentage discount on the purchase order value</b>
     */
    @Override
    public boolean isDiscountType_PercentageDiscountOnThePurchaseOrderValue(InvoiceTotal_model model) {
        return model.isDiscountPercent();
    }

    /**
     * <b>C04: Discount &lt; purchase order value</b><br>
     * <br>
     * <b>C04/01: Y - Yes</b>
     */
    @Override
    public boolean isDiscountLessPurchaseOrderValue(InvoiceTotal_model model) {
        return model.getOrderDiscount().compareTo(model.getOrderValue()) < 0;
    }

    /**
     * <b>A01: Apply discount</b>
     */
    @Override
    public void doApplyDiscount(InvoiceTotal_model model) {
        model.setTotalDiscount(model.isDiscountPercent()

                ? model.getOrderValue()
                .multiply(model.getOrderDiscount())
                .multiply(bigDecimal(0.01))
                .setScale(2, RoundingMode.HALF_UP)

                : model.getOrderDiscount());
    }

    /**
     * <b>A02: Calculate shipping costs</b>
     */
    @Override
    public void doCalculateShippingCosts(InvoiceTotal_model model) {
        model.setTotalPostage(model.getPostage());
    }

    /**
     * <b>A03: Invoice total</b><br>
     * <br>
     * <b>A03/01: upd - Invoice total must be updated</b>
     */
    @Override
    public void doInvoiceTotal_Upd(InvoiceTotal_model model) {
        model.setTotalAmount(model.getOrderValue()
                .subtract(model.getTotalDiscount())
                .add(model.getTotalPostage()));
    }

    /**
     * <b>A03: Invoice total</b><br>
     * <br>
     * <b>A03/02: pov - Purchase order value can be taken over as invoice total</b>
     */
    @Override
    public void doInvoiceTotal_Pov(InvoiceTotal_model model) {
        model.setTotalAmount(model.getOrderValue());
    }

    /**
     * @param dtName  - the decision table name
     * @param version - the timestamp of program generation
     * @param rules   - the number of rules in the decision table
     * @param rule    - the rule which is executed now
     */
    @Override
    public void doTrace(String dtName, String version, int rules, int rule, InvoiceTotal_model model) {
        System.out.printf("%s, %s, %d, %d, %s\n", dtName, version, rules, rule, model);
    }

    /**
     * @param dtName  - the decision table name
     * @param version - the timestamp of program generation
     * @param rules   - the number of rules in the decision table
     * @param rule    - the rule which is executed now
     */
    @Override
    public void doTraceAfterRule(String dtName, String version, int rules, int rule, InvoiceTotal_model model) {
        System.out.printf("%36s %s\n\n", "", model);
    }
}