hibernate 一对一关联关系 及其懒加载，总结

<hibernate-mapping package="cn.itcast.hibernate.domain">

<class name="Person">
<id name="id">
<generator class="native" />
</id>
<property name="name" />
<one-to-one name="idCard"/>
</class>

</hibernate-mapping>

<hibernate-mapping package="cn.itcast.hibernate.domain">

<class name="IdCard" table="id_card">
<id name="id">
<generator class="foreign">
<param name="property">person</param>
</generator>

</id>
<property name="name"/>

<one-to-one name="person" constrained = "true"/>
</class>

</hibernate-mapping>