Hibernate学习笔记-------继承关系映射

继承关系映射配置实例------------>

<?xml version="1.0"?> <!DOCTYPE hibernate-mapping PUBLIC "-//Hibernate/Hibernate Mapping DTD 3.0//EN" "http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd"> <hibernate-mapping package="com.xx.domain"> <!-- 继承关系之映射成一张表 --> <!-- 父类的也必须加上discriminator-value属性 --> <class name="Animal" table="t_animal" discriminator-value="0"> <id name="id"> <generator class="native" /> </id> <discriminator column="type" type="int"/> <property name="name"/> <subclass name="Pepole" discriminator-value="1"> <property name="sex" ></property> </subclass> <subclass name="Dog" discriminator-value="2"> <property name="age" ></property> </subclass> </class> <!-- 继承关系之每个子类映射成一张表 --> <!-- <class name="Animal" table="t_animal"> <id name="id"> <generator class="native" /> </id> <property name="name"/> <joined-subclass name="Pepole"> <key column="animalid"/> <property name="sex"></property> </joined-subclass> <joined-subclass name="Dog"> <key column="animalid"/> <property name="age"></property> </joined-subclass> </class> --> <!-- 继承关系之鉴别器与内连接相结合 --> <!-- <class name="Animal" table="t_animal" discriminator-value="0"> <id name="id"> <generator class="native" /> </id> <discriminator column="type" type="int"/> <property name="name"/> <subclass name="Pepole" discriminator-value="1"> <property name="sex" ></property> </subclass> <subclass name="Dog" discriminator-value="2"> <join table="dog"> <key column="anmimalid"/> <property name="age" ></property> </join> </subclass> </class> --> <!-- 每个具体类映射一张独立表 --> <!-- 子类的表和父类的表的id不能重复，所以不能用自增 --> <!-- <class name="Animal" table="t_animal"> <id name="id"> <generator class="hilo" /> </id> <property name="name"/> <union-subclass name="Pepole"> <property name="sex"/> </union-subclass> <union-subclass name="Dog"> <property name="age"/> </union-subclass> </class> --> </hibernate-mapping>