Hibernate多态查询

<?xmlversion="1.0"encoding="UTF-8"?>

<!DOCTYPEhibernate-mappingPUBLIC"-//Hibernate/HibernateMappingDTD3.0//EN""http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd">

<hibernate-mapping>

<classname="net.gehua.weixin.model.sendMsg.SendMsg"table="t_send_msg"lazy="false">

<idname="id"type="java.lang.Long">

<generatorclass="increment"/>

</id>

<!--鉴别器字段,必须放在id后面.子类中要添加discriminator-value="?",给鉴别器字段赋值-->

<discriminatorcolumn="type"type="string"/><!--这里的string类型是Hibernate的类型,全小写-->

<propertyname="msgType"/>

<propertyname="createTime"column="create_time"/>

<propertyname="updateTime"column="update_time"/>

<subclassname="net.gehua.weixin.model.sendMsg.SendImageMsg"discriminator-value="SendImageMsg">

<propertyname="mediaId"/>

</subclass>

<subclassname="net.gehua.weixin.model.sendMsg.SendTextMsg"discriminator-value="SendTextMsg">

<propertyname="content"/>

</subclass>

</class>

</hibernate-mapping>

class属性一定要添加lazy="false"get方法才支持多态查询