tadas-subonis

class OrderPlacedEvent {
        private Order order;
    }

    class ShopSellerService {

        @Inject
        private EventBus eventBus;

        public void sell(Order order) {

tadas-subonis

    class ShopSellerService {

        @Inject
        @SMS
        private Notifier notifier;

        public void sell(Order order) {
            order.toPlaced();

            notifier.sendOrderPlacedNotification(order.getCustomer());

tadas-subonis

        class Order {
            Item[] items;
            String orderId;
            Customer customer;

            void addItem(Item item) {
            }

            double getTotalPrice() {
                //...

tadas-subonis

        class Order {
            Item[] items;
            String orderId;
            Customer customer;
            Double totalPrice;

            void addItem(Item item) {
                //...
                totalPrice = null;
            }

tadas-subonis

        //regular customer
        class Customer {
            private String name;
            String getName() {
                return name;
            }
            boolean canCancelDispatchedOrder() {
                return false;
            }
        }

tadas-subonis

        class Customer {
            String name;
        }

        class Item {
            String sku;
            BigDecimal price;
        }

        class Order {

tadas-subonis

        //domain
        package com.company.bigproject.domain;
        //or just
        package com.company.bigproject;
        //[...]

        //presentation
        package com.company.bigproject.web;
        //[...]

tadas-subonis

        //regular customer
        class Customer {
            private String name;
            String getName() {
                return name;
            }
            boolean canCancelDispatchedOrder() {
                return false;
            }
        }

tadas-subonis

        String orderId = request.getParam("id");
        String sku = request.getParam("sku");
        Order order = orderDao.findOneById(orderId);
        Item item = itemDao.findOneBySku(sku);

        order.addItem(item);

        double total = 0.0;
        for (Item item : order.getItems()) {
            total += item.getPrice();

tadas-subonis

        class Order {
            Item[] items;
            String orderId;
            Customer customer;
            Double totalPrice;

            void addItem(Item item) {
                //...
                totalPrice = null;
            }