Hibernate学习笔记：继承映射之每个子类一张表,使用辨别标志

<hibernate-mapping package="model">
<class name="Animal" table="animal1" schema="dbo" catalog="hibernate">
<id name="id" column="id">
<generator class="native" />
</id>
<discriminator column="animal_type" type="string" />
<property name="name" />
<many-to-one name="zoo" class="model.Zoo" column="zoo_id" />
<subclass name="model.Monkey" discriminator-value="MONKEY">
<join table="monkey">
<key column="animal_id" />
<property name="age" />
</join>
</subclass>
<subclass name="model.Tiger" discriminator-value="TIGER">
<join table="tiger">
<key column="animal_id" />
<property name="kind" />
</join>
</subclass>
</class>
</hibernate-mapping>
<!--
alter table animal1 add animal_type varchar(10)
update animal1 set animal_type='TIGER' where id >=6
alter table animal1 alter column animal_type varchar(10) not null
-->

public static void main(String[] args){
AnimalDao dao = new AnimalHibernateDao();
List l = dao.listMonkdy();
System.out.println(l.size());
Monkey m = new Monkey();
Zoo z = dao.getZooById(1);
m.setAge(14);
m.setName("jinggang");
m.setZoo(z);
dao.save(m);
}