我正在hibernate的帮助下开发一个电子购物程序。因为我是jsp、servlet、hibernate的新手,我不知道如何使用关系表中的附加列进行多对多关系映射。我已经阅读了几篇教程,但其中大部分都是关于hibernate社区的注释映射和文档,但没有一篇适合我的情况。
我有三个表,分别是电影信息表、订单详情表和订单详情表(关系表),其中订单详情表的结构如下所示。
order_details
-------------
order_id FK
movie_id FK
quantity
-------------
我正在尝试使用四个POJO类来实现多对多关系。代码来了。
电影信息。Java语言
// other variable, constructor, getter, setter
private Set<OrderDetails> orderDetails = new HashSet<OrderDetails>();
顺序Java语言
// other variable, constructor, getter, setter
private Set<OrderDetails> orderDetails = new HashSet<OrderDetails>();
订单Details.java
private OrderDetailsPK primaryKey;
private Order order;
private MovieInformation movie;
private int quantity;
OrderDetailsPK。Java语言
private long orderId;
private long movieId;
电影信息。hbm。xml
<id column="movie_id" name="movieId" type="long">
<generator class="native"/>
</id>
// some property
<set name="orderDetails" table="order_details" inverse="true" lazy="true" fetch="select">
<key>
<column name="movie_id" not-null="true" />
</key>
<one-to-many class="cart.hibernate.orderDetails.orderDetails" />
</set>
顺序hbm。xml
<id column="order_id" name="orderId" type="long">
<generator class="native"/>
</id>
//some properties
<set name="orderDetails" table="order_details" inverse="true" lazy="true" fetch="select">
<key>
<column name="order_id" not-null="true" />
</key>
<one-to-many class="cart.hibernate.orderDetails.orderDetails" />
</set>
订单Details.hbm.xml
<composite-id name="orderDetailsPK" class="cart.hibernate.orderDetailsPK.OrderDetailsPK">
<key-property column="order_id" name="orderId" type="long"/>
<key-property column="movie_id" name="movieId" type="long"/>
</composite-id>
<many-to-one name="order" class="cart.hibernate.order.Order" insert="false" update="false"/>
<many-to-one name="movie" class="cart.hibernate.movieInformation.MovieInformation" insert="false" update="false"/>
<property column="quantity" name="quantity" type="int"/>
OrderDetailsPK。hbm。xml
<class name="cart.hibernate.orderDetailsPK.OrderDetailsPK" >
<property name="orderId" type="long"/>
<property name="movieId" type="long"/>
hibernate.cfg.cml
<mapping class="cart.hibernate.MovieInformation" package="cart.hibernate.movieInformation" resource="cart/hibernate/movieInformation/MovieInformation.hbm.xml"/>
<mapping class="cart.hibernate.Order" package="cart.hibernate.order" resource="cart/hibernate/order/Order.hbm.xml"/>
<mapping class="cart.hibernate.OrderDetails" package="cart.hibernate.orderDetails" resource="cart/hibernate/orderDetails/OrderDetails.hbm.xml"/>
<mapping class="cart.hibernate.OrderDetailsPK" package="cart.hibernate.orderDetailsPK" resource="cart.hibernate.orderDetailsPK/OrderDetailsPK.hbm.xml"/>
当我尝试运行测试main方法时,程序引发了异常
887 [main] INFO org.hibernate.cfg.Configuration - Reading mappings from resource :
cart.hibernate.orderDetailsPK/OrderDetailsPK.hbm.xml
Initial SessionFactory creation failed.org.hibernate.MappingNotFoundException: resource: cart.hibernate.orderDetailsPK/OrderDetailsPK.hbm.xml not found
Exception in thread "main" java.lang.ExceptionInInitializerError
at cart.hibernate.HibernateUtil.buildSessionFactory(HibernateUtil.java:28)
at cart.hibernate.HibernateUtil.<clinit>(HibernateUtil.java:18)
at cart.hibernate.order.ManageOrder.main(ManageOrder.java:40)
Caused by: org.hibernate.MappingNotFoundException: resource: cart.hibernate.orderDetailsPK/OrderDetailsPK.hbm.xml not found
at org.hibernate.cfg.Configuration.addResource(Configuration.java:799)
at org.hibernate.cfg.Configuration.parseMappingElement(Configuration.java:2344)
at org.hibernate.cfg.Configuration.parseSessionFactory(Configuration.java:2310)
at org.hibernate.cfg.Configuration.doConfigure(Configuration.java:2290)
at org.hibernate.cfg.Configuration.doConfigure(Configuration.java:2243)
at org.hibernate.cfg.Configuration.configure(Configuration.java:2158)
at cart.hibernate.HibernateUtil.buildSessionFactory(HibernateUtil.java:23)
... 2 more
在我阅读了其他人提出的问题后,我相信我的代码中的错误是由错误的映射代码引起的。希望你们能帮助我解决这个问题。如果提供一些带有额外列的多对多映射的简单示例就好了。
我相信你的代码是干净的,因为控制台告诉你MappingNotFoundException
一旦加载了hibernate文件,就找不到了。确保模型bean包中的hibernate文件不在源代码中。