ddd to view

MonthlyCostsDenormalizer.java

//an event
// new ItemAdded("item-id-34", 45$, "2014-10-21-18:47:12")

//the handler

public class MonthlyCostsDenormalizer implements IHandle<ItemAddedToCart> {

    private MonthlyCostsDao dao

    public MonthlyCostsDenormalizer(MonthlyCostsDao dao) {
        this.dao = dao;
    }

    public void handle(ItemAddedToCart) {
        MonthlyCosts view = dao.getById(parseYearAndMonth(item.getHappenedAt()));

        view.add(item.getCost());

        repository.update(view);

    }

    private static String parseYearAndMonth(DateTime date) {
        // for the example returns "2014-10"
    }

}