单向关联的hibernate映射如何实现。急求教！谢谢

    /// <summary>
    /// 订单
    /// </summary>
    public class Order
    {
        public Money Amount { get; set; }
        //……
        /// <summary>
        /// 收件人信息（存储在与订单一对一对关系的一张数据表中）
        /// </summary>
        public Consigneee Consignee { get; set; }
    }

    /// <summary>
    /// 收件人
    /// </summary>
    public class Consignee
    {
        public virtual string ConsigneeName { get; set; }
        public virtual string Address { get; set; }
    }