Hibernate 一对多外键单向关联
来源:互联网 发布:压缩 linux 编辑:程序博客网 时间:2024/05/29 03:41
Hibernate 一对多外键单向关联
这种情况很少见,但Hibernate同样允许采用连接表关联1-1.有连接表的1-1同样只需要将N-1的many-to-one元素增加unique="true"属性即可。
一、模型介绍
一个人(Person)对应多个地址(Address),比如家庭地址、公司地址。
二、实体(省略getter、setter方法)
public class Person1nfk implements Serializable {
private int personid;
private String name;
private int age;
private Set addresses=new HashSet();
public class Address1nfk implements Serializable {
private int addressid;
private String addressdetail;
三、表模型
mysql> desc address_1nfk;
+---------------+--------------+------+-----+---------+----------------+
| Field | Type | Null | Key | Default | Extra |
+---------------+--------------+------+-----+---------+----------------+
| addressid | int(11) | NO | PRI | NULL | auto_increment |
| addressdetail | varchar(255) | YES | | NULL | |
| personid | int(11) | YES | MUL | NULL | |
+---------------+--------------+------+-----+---------+----------------+
mysql> desc person_1nfk;
+----------+--------------+------+-----+---------+----------------+
| Field | Type | Null | Key | Default | Extra |
+----------+--------------+------+-----+---------+----------------+
| personid | int(11) | NO | PRI | NULL | auto_increment |
| name | varchar(255) | YES | | NULL | |
| age | int(11) | YES | | NULL | |
+----------+--------------+------+-----+---------+----------------+
四、生成的SQL脚本
/* Formatted on 2007/08/21 10:06 (QP5 v5.50) */
CREATE TABLE `address_1nfk` (
`addressid` int(11) NOT NULL auto_increment,
`addressdetail` varchar(255) default NULL,
`addresses` int(11) default NULL,
PRIMARY KEY (`addressid`),
KEY `FK9B93456DC08D1667` (`addresses`),
CONSTRAINT `FK9B93456DC08D1667` FOREIGN KEY (`addresses`) REFERENCES `person_1nfk` (`personid`)
) ENGINE=InnoDB AUTO_INCREMENT=3 DEFAULT CHARSET=gbk;
/* Formatted on 2007/08/21 10:07 (QP5 v5.50) */
CREATE TABLE `person_1nfk` (
`personid` int(11) NOT NULL auto_increment,
`name` varchar(255) default NULL,
`age` int(11) default NULL,
PRIMARY KEY (`personid`)
) ENGINE=InnoDB AUTO_INCREMENT=2 DEFAULT CHARSET=gbk;
五、映射方法:在实体类Person里面添加Address的集合,即可形成一对多关系。
<!--映射集合属性,关联到持久化类,inverse="false"表示主控端在Person1nfk端,lazy="false"表示不采用延迟加载-->
<set name="addresses"
table="ADDRESS_1nfk"
cascade="all"
>
<!--确定关联的外键列-->
<key column="personid"/>
<!--用以映射到关联类属性-->
<one-to-many class="com.lavasoft.dx._1_n_fk.Address1nfk"/>
</set>
<hibernate-mapping>
<class name="com.lavasoft.dx._1_n_fk.Person1nfk" table="PERSON_1nfk">
<id name="personid">
<generator class="identity"/>
</id>
<property name="name"/>
<property name="age"/>
<!--映射集合属性,关联到持久化类,inverse="false"表示主控端在Person1nfk端,lazy="false"表示不采用延迟加载-->
<set name="addresses"
table="ADDRESS_1nfk"
cascade="all"
>
<!--确定关联的外键列-->
<key column="personid"/>
<!--用以映射到关联类属性-->
<one-to-many class="com.lavasoft.dx._1_n_fk.Address1nfk"/>
</set>
</class>
</hibernate-mapping>
<hibernate-mapping>
<class name="com.lavasoft.dx._1_n_fk.Address1nfk" table="ADDRESS_1nfk">
<id name="addressid">
<generator class="identity"/>
</id>
<property name="addressdetail"/>
</class>
</hibernate-mapping>
六、测试方法
public class Test_1nfk {
public static void main(String[] args){
Address1nfk add1=new Address1nfk();
Address1nfk add2=new Address1nfk();
Person1nfk p=new Person1nfk();
add1.setAddressdetail("郑州市经三路");
add2.setAddressdetail("合肥市宿州路");
p.setName("wang");
p.setAge(30);
p.getAddresses().add(add1);
p.getAddresses().add(add2);
Session session= HibernateUtil.getCurrentSession();
Transaction tx=session.beginTransaction();
session.save(add1);
session.save(add2);
session.save(p);
tx.commit();
HibernateUtil.closeSession();
}
}
七、测试结果
1) :正常保存.
// session.save(add1);
// session.save(add2);
session.save(p);
Hibernate: insert into PERSON_1nfk (name, age) values (?, ?)
Hibernate: insert into ADDRESS_1nfk (addressdetail) values (?)
Hibernate: insert into ADDRESS_1nfk (addressdetail) values (?)
Hibernate: update ADDRESS_1nfk set personid=? where addressid=?
Hibernate: update ADDRESS_1nfk set personid=? where addressid=?
2) :正常保存.
session.save(add1);
session.save(add2);
session.save(p);
Hibernate: insert into ADDRESS_1nfk (addressdetail) values (?)
Hibernate: insert into ADDRESS_1nfk (addressdetail) values (?)
Hibernate: insert into PERSON_1nfk (name, age) values (?, ?)
Hibernate: update ADDRESS_1nfk set personid=? where addressid=?
Hibernate: update ADDRESS_1nfk set personid=? where addressid=?
3) :正常保存.
session.save(add1);
session.save(add2);
// session.save(p);
Hibernate: insert into ADDRESS_1nfk (addressdetail) values (?)
Hibernate: insert into ADDRESS_1nfk (addressdetail) values (?)
0 0
- Hibernate 一对多外键单向关联
- Hibernate 一对多外键单向关联
- Hibernate 一对多外键单向关联
- Hibernate 一对多外键单向关联
- Hibernate关联之 一对多外键单向关联
- Hibernate一对多单向关联
- hibernate一对多单向关联
- hibernate一对多单向关联
- Hibernate单向一对多关联
- hibernate一对多单向关联
- Hibernate 一对多单向关联
- hibernate 关联关系 一对多 单向关联 .
- hibernate中----一对多单向关联,一对多双向关联
- Hibernate一对多单向关联映射
- Hibernate一对多的单向关联
- Hibernate映射一对多单向关联(之一)
- Hibernate一对多关联映射—单向
- hibernate一对多关联映射—单向
- Hibernate 笔记二(多表设计之一对多)
- android 资源文件处理工具
- 国密SKF接口函数介绍之二:访问控制函数
- laravel使用七牛组件上传图片
- Java 并发:线程间通信与协作
- Hibernate 一对多外键单向关联
- 关于我及新年计划
- 运维进阶
- 26.图文混排
- Hibernate 一对多连接表单向关联
- 程序或-内存区域分配(五个段)
- Android PopupWindow背景半透明兼容方案
- Java无需解压直接读取Zip文件和文件内容
- 微信小程序开发(二):获取微信小程序页面带参二维码全流程