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我想实现父母的标准功能，就像它的孩子的拥有实体一样，就像对Order- OrderLine。我想在一个视图中修改订单和订单行，并仅提供基于版本字段的乐观锁定Order。我还想将索引列表用作索引存储在数据库中的集合。

我尝试了不同的设置，但都没有奏效。我的设置是：

数据库脚本：

CREATE TABLE Site_Order (
    order_id INT NOT NULL PRIMARY KEY AUTO_INCREMENT,
    order_number INT NOT NULL,
    version BIGINT NOT NULL
)ENGINE=InnoDB DEFAULT CHARSET=utf8;

INSERT INTO Site_Order (order_number, version) VALUES (1, 1);

CREATE TABLE Order_Line (
    order_line_id INT NOT NULL PRIMARY KEY AUTO_INCREMENT,
    order_id INT NOT NULL,
    product_name VARCHAR(100),
    idx INT NOT NULL,
    FOREIGN KEY (order_id) REFERENCES Site_Order(order_id) ON UPDATE CASCADE ON DELETE CASCADE
)ENGINE=InnoDB DEFAULT CHARSET=utf8;

INSERT INTO Order_Line (order_id, product_name, idx) VALUES (1, "Coffee", 0);

实体：

@Entity @Table(name = "site_order")
public class SiteOrder implements java.io.Serializable {

    private Integer orderId;
    private int orderNumber;
    private long version;
    private List<OrderLine> orderLines = new ArrayList<OrderLine>(0);

    //constructors, fileds getters and setters

    @OneToMany(fetch = FetchType.LAZY, orphanRemoval=true)
    @Cascade({CascadeType.SAVE_UPDATE, CascadeType.DELETE, CascadeType.MERGE})
    @OrderColumn(name="idx", nullable=false)
    @JoinColumn(name="order_id", nullable=false)
    public List<OrderLine> getOrderLines() {
        return this.orderLines;
    }

    protected void setOrderLines(List<OrderLine> orderLines) {
        this.orderLines = orderLines;
    }

    public void addOrderLine(OrderLine ol) {
        orderLines.add(ol);
        if (!orderLine.getSiteOrder().equals(this)) {
            orderLine.getSiteOrder().getOrderLines().remove(orderLine);
            orderLine.setSiteOrder(this);
        }
    }

    public void removeOrderLine(OrderLine ol) {
        orderLines.remove(ol);
        if (orderLine.getSiteOrder().equals(this)) {
            orderLine.setSiteOrder(null);
        }
    }

}

@Entity @Table(name = "order_line")
public class OrderLine implements java.io.Serializable {

    private Integer orderLineId;
    private SiteOrder siteOrder;
    private String productName;

    //constructors, fileds getters and setters

    @ManyToOne(fetch = FetchType.LAZY)
    @JoinColumn(name = "order_id", nullable = false, insertable=false, updatable=false)
    public SiteOrder getSiteOrder() {
        return this.siteOrder;
    }

    public void setSiteOrder(SiteOrder siteOrder) {
        this.siteOrder = siteOrder;
        if ((siteOrder != null) && (!siteOrder.getOrderLines().contains(this))) {
            siteOrder.addOrderLine(this);
        }
    }

}

典型用法是 (1) 向现有订单添加新订单行，其中订单版本得到更新； (2) 修改订单行的属性，如数量、产品、价格等，不影响订单版本。

(1):

Session session = HibernateUtil.getSessionFactory().openSession();
session.beginTransaction();
SiteOrder s = (SiteOrder)session.get(SiteOrder.class, Integer.valueOf(1));
OrderLine o = new OrderLine();
o.setProductName("Cup");
s.addOrderLine(o);
session.getTransaction().commit();
session.close();

(2):

Session session = HibernateUtil.getSessionFactory().openSession();
session.beginTransaction();
SiteOrder s = (SiteOrder)session.get(SiteOrder.class, Integer.valueOf(1));
s.getOrderLines().get(0).setProductName("Tea");
session.getTransaction().commit();
session.close();

有没有办法在 Hibernate 中实现上述版本控制问题的通用解决方案？

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