| 一、模型介紹 |
| 多個人（Person）對應(yīng)一個地址（Address）。 |
| 二、實體（省略getter、setter方法） |
| public class Personn1tab { |
| PRivate int personid; |
| private String name; |
| private int age; |
| private Addressn1tab addressn1tab; |
| public class Addressn1tab { |
| private int addressid; |
| private String addressdetail; |
| 三、表模型 |
| MySQL> desc address_n1tab; |
| +---------------+--------------+------+-----+---------+----------------+ |
| | Field | Type | Null | Key | Default | Extra | |
| +---------------+--------------+------+-----+---------+----------------+ |
| | addressid | int(11) | NO | PRI | NULL | auto_increment | |
| | addressdetail | varchar(255) | YES | | NULL | | |
| +---------------+--------------+------+-----+---------+----------------+ |
| mysql> desc join_n1tab; |
| +------------+---------+------+-----+---------+-------+ |
| | Field | Type | Null | Key | Default | Extra | |
| +------------+---------+------+-----+---------+-------+ |
| | personid | int(11) | NO | PRI | | | |
| | addressn1tab | int(11) | YES | MUL | NULL | | |
| +------------+---------+------+-----+---------+-------+ |
| mysql> desc person_n1tab; |
| +----------+--------------+------+-----+---------+----------------+ |
| | 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腳本 |
| CREATE TABLE `address_n1tab` ( |
| `addressid` int(11) NOT NULL auto_increment, |
| `addressdetail` varchar(255) default NULL, |
| PRIMARY KEY (`addressid`) |
| ) ENGINE=InnoDB AUTO_INCREMENT=2 DEFAULT CHARSET=gbk; |
| CREATE TABLE `join_n1tab` ( |
| `personid` int(11) NOT NULL, |
| `address11fk` int(11) default NULL, |
| PRIMARY KEY (`personid`), |
| KEY `FKAC780AAADAE3A82C` (`personid`), |
| KEY `FKAC780AAAC6242A64` (`address11fk`), |
| CONSTRAINT `FKAC780AAAC6242A64` FOREIGN KEY (`address11fk`) REFERENCES `address_n1tab` (`addressid`), |
| CONSTRAINT `FKAC780AAADAE3A82C` FOREIGN KEY (`personid`) REFERENCES `person_n1tab` (`personid`) |
| ) ENGINE=InnoDB DEFAULT CHARSET=gbk; |
| CREATE TABLE `person_n1tab` ( |
| `personid` int(11) NOT NULL auto_increment, |
| `name` varchar(255) default NULL, |
| `age` int(11) default NULL, |
| PRIMARY KEY (`personid`) |
| ) ENGINE=InnoDB AUTO_INCREMENT=3 DEFAULT CHARSET=gbk; |
| 五、映射方法 |
| <hibernate-mapping> |
| <class name="com.lavasoft.dx._n_1_tab.Personn1tab" table="PERSON_n1tab"> |
| <id name="personid"> |
| <generator class="identity"/> |
| </id> |
| <property name="name"/> |
| <property name="age"/> |
| <!--使用join元素顯式確定鏈接表--> |
| <join table="join_n1tab"> |
| <!--映射關(guān)聯(lián)所用的外鍵--> |
| <key column="personid"/> |
| <many-to-one name="addressn1tab"/> |
| </join> |
| </class> |
| </hibernate-mapping> |
| <hibernate-mapping> |
| <class name="com.lavasoft.dx._n_1_tab.Addressn1tab" table="ADDRESS_n1tab"> |
| <id name="addressid"> |
| <generator class="identity"/> |
| </id> |
| <property name="addressdetail"/> |
| </class> |
| </hibernate-mapping> |
| 六、測試方法 |
| public class Test_n1tab { |
| public static void main(String[] args){ |
| Personn1tab p1=new Personn1tab(); |
| Personn1tab p2=new Personn1tab(); |
| p1.setAge(21); |
| p1.setName("p1"); |
| p2.setAge(23); |
| p2.setName("p2"); |
| Addressn1tab add=new Addressn1tab(); |
| add.setAddressdetail("鄭州市經(jīng)三路"); |
| p1.setAddressn1tab(add); |
| p2.setAddressn1tab(add); |
| session session=HibernateUtil.getCurrentSession(); |
| Transaction tx=session.beginTransaction(); |
| session.save(add); |
| session.save(p1); |
| session.save(p2); |
| tx.commit(); |
| HibernateUtil.closeSession(); |
| } |
| } |
| 七、測試結(jié)果 |
| 1) :正常保存. 推薦這么干! |
| session.save(p1); |
| session.save(p2); |
| Hibernate: insert into ADDRESS_n1tab (addressdetail) values (?) |
| Hibernate: insert into PERSON_n1tab (name, age) values (?, ?) |
| Hibernate: insert into join_n1tab (address11fk, personid) values (?, ?) |
| Hibernate: insert into PERSON_n1tab (name, age) values (?, ?) |
| Hibernate: insert into join_n1tab (address11fk, personid) values (?, ?) |
| 2) :正常保存. |
| session.save(p1); |
| session.save(p2); |
| session.save(add); |
| Hibernate: insert into PERSON_n1tab (name, age) values (?, ?) |
| Hibernate: insert into join_n1tab (address11fk, personid) values (?, ?) |
| Hibernate: insert into PERSON_n1tab (name, age) values (?, ?) |
| Hibernate: insert into join_n1tab (address11fk, personid) values (?, ?) |
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