hibernate基础10:关联映射之基于主键的双向一对一
Posted 来临
tags:
篇首语:本文由小常识网(cha138.com)小编为大家整理,主要介绍了hibernate基础10:关联映射之基于主键的双向一对一相关的知识,希望对你有一定的参考价值。
Java实体bean类
package com.project.pojo; import java.io.Serializable; public class Card implements Serializable{ private String id; private String address; private Person person; public String getId() { return id; } public void setId(String id) { this.id = id; } public String getAddress() { return address; } public void setAddress(String address) { this.address = address; } public Person getPerson() { return person; } public void setPerson(Person person) { this.person = person; } }
package com.project.pojo; import java.io.Serializable; public class Person implements Serializable{ private String id ; private String name; private String sex; private Card card; public String getId() { return id; } public void setId(String id) { this.id = id; } public String getName() { return name; } public void setName(String name) { this.name = name; } public String getSex() { return sex; } public void setSex(String sex) { this.sex = sex; } public Card getCard() { return card; } public void setCard(Card card) { this.card = card; } }
2、配置hbm.xml
<?xml version="1.0" encoding="UTF-8"?> <!DOCTYPE hibernate-mapping PUBLIC "-//Hibernate/Hibernate Mapping DTD 3.0//EN" "http://www.hibernate.org/dtd/hibernate-mapping-3.0.dtd"> <hibernate-mapping package="com.project.pojo"> <class name="Card" table="t_card"> <id name="id"> <generator class="assigned" /> </id> <property name="address" /> <one-to-one name="person" /> </class> </hibernate-mapping>
<?xml version="1.0" encoding="UTF-8"?> <!DOCTYPE hibernate-mapping PUBLIC "-//Hibernate/Hibernate Mapping DTD 3.0//EN" "http://www.hibernate.org/dtd/hibernate-mapping-3.0.dtd"> <hibernate-mapping package="com.project.pojo"> <class name="Person" table="t_person"> <id name="id"> <generator class="foreign"> <param name="property">card</param> </generator> </id> <property name="name" /> <property name="sex" /> <!-- 基于主键的一对一 constrained为true时将添加外键约束 --> <one-to-one name="card" constrained="true"></one-to-one> </class> </hibernate-mapping>
3、测试
package com.project.test;
import org.hibernate.Session;
import org.hibernate.Transaction;
import org.hibernate.cfg.Configuration;
import org.hibernate.tool.hbm2ddl.SchemaExport;
import org.junit.After;
import org.junit.Before;
import org.junit.Test;
import com.project.pojo.Card;
import com.project.pojo.Person;
import com.project.util.HibernateUtil;
public class HibernateTest {
Session session = null;
Transaction ts = null;
@Before
public void setUp(){
session = HibernateUtil.getSession();
ts = session.beginTransaction();
}
@After
public void tearDown(){
HibernateUtil.closeSession();
}
@Test
public void testCreateDB(){
Configuration cfg = new Configuration().configure();
//使得hibernate映射信息转换为数据库识别的dll语言
SchemaExport se = new SchemaExport(cfg);
//第一个参数:是否打印dll语句
//第二个参数:是否将dll到数据库中执行
se.create(true, true);
}
@Test
public void testInit(){
try {
Card c1 = new Card();
c1.setId("1001");
c1.setAddress("xx市1区");
Card c2 = new Card();
c2.setId("1002");
c2.setAddress("xx市2区");
session.save(c1);
session.save(c2);
Person p1 = new Person();
p1.setName("张三");
p1.setSex("男");
p1.setCard(c1);
Person p2 = new Person();
p2.setName("李四");
p2.setSex("男");
p2.setCard(c2);
session.save(p1);
session.save(p2);
ts.commit();
} catch (Exception e) {
e.printStackTrace();
if(ts!=null)ts.rollback();
}
}
@Test
public void testSelect(){
Person p = (Person)session.get(Person.class, "1001");
System.out.println(p.getName()+" "+p.getSex());
System.out.println("---------------");
System.out.println(p.getCard().getAddress());
System.out.println("=================");
Card c = (Card)session.get(Card.class, "1001");
System.out.println(c.getAddress());
System.out.println("---------------");
System.out.println(c.getPerson().getName()+" "+c.getPerson().getSex());
}
}
以上是关于hibernate基础10:关联映射之基于主键的双向一对一的主要内容,如果未能解决你的问题,请参考以下文章