Hibernate中使用的集合类型

department与employee是一对多关系。

set

<set name="emps" inverse="true">
        <key column="depart_id"/>
        <one-to-many class="Employee" />
</set>

list，关键在于有一定顺序：

<list name="emps">
        <key column="depart_id" />
        <list-index column="order_col" />
        <one-to-many class="Employee" />
</list>

所以需要配置<list-index column="order_col" />

map： Map<Strig,Employee> emps;

<map name="emps">
    <key column="depart_id" />
    <map-key type="string" column="name"/>
    <one-to-many class="Employee" />
</map>

bag:想用list又不需要保证顺序

<bag name="emps">
    <key column="depart_id" />
    <one-to-many class="Employee" />
</bag>