Hibernate实体映射

1，设计实体/表
2，Dao
3，Service
4，Action
5，JSP

模板：


多对一：
<many-to-one name="" class="" column=""></many-to-one>
一对多：
<set name="">
<key column=""></key>
<one-to-many class=""/>
</set>
多对多：
<set name="" table="">
<key column=""></key>
<many-to-many class="" column=""></many-to-many>
</set>

name属性：属性名

class属性：关联的实体类型

column属性：

many-to-one  column=""   一般写成属性名加Id后缀

一对多 时则对方就是多对一 只需要把对方的映射拷贝到column

Role.hbm.xml

<!-- department属性，本类与Department的多对一 -->
<many-to-one name="department" class="Department" column="departmentId"></many-to-one>


<!-- roles属性，本类与Role的多对多 -->
<set name="roles" table="itlan_user_role">
<key column="userId"></key>
<many-to-many class="Role" column="roleId"></many-to-many>
</set>

User.hbm.xml

<!-- department属性，本类与Department的多对一 -->
<many-to-one name="department" class="Department" column="departmentId"></many-to-one>


<!-- roles属性，本类与Role的多对多 -->
<set name="roles" table="itlan_user_role">
<key column="userId"></key>
<many-to-many class="Role" column="roleId"></many-to-many>
</set>

Department.hbm.xml

<!-- users属性，本类与User的一对多 -->
<set name="users">
<key column="departmentId"></key>
<one-to-many class="User" />
</set>


<!-- parent属性，本类与Department（上级）的多对一 -->
<many-to-one name="parent" class="Department" column="parentId"></many-to-one>


<!-- children属性，本类与Department（下级）的一对多 -->
<set name="children">
<key column="parentId"></key>
<one-to-many class="Department" />
</set>