public class Sale
{
    private Long id;
    private Date soldDate;
    private List<SalesUnit> sales;

    public Sale(List sales)
    {
        soldDate=new Date();
        this.sales=sales;
    }
    public Sale()
    {
        soldDate=new Date();
    }
}

public class SalesUnit
{
    private Long salesID;
    private Item item;
    private Long quantity;
    private Double total;
    private Float discount;
    /** Creates a new instance of SalesUnit */
    public SalesUnit(Item item,Long quantity)
    {
        this.quantity=quantity;
        this.item=item;
       
    }
    public SalesUnit()
    {

    }
}