【7.4.1】基于外键的双向一对一的关联映射

1.公民表person 和身份证 IdCard

 

 

2.类Person 和IdCard类

public class Person {
	private int id;
	private String name;
	private int age;
	private IdCard idCard;
//get…set
}



public class IdCard{
	private int id;
	private String code;
   private Person person;

	//get…set
}

 

3.配置文件

IdCard.hbm.xml

<?xml version="1.0"?>
<!DOCTYPE hibernate-mapping PUBLIC 
	"-//Hibernate/Hibernate Mapping DTD 3.0//EN"
	"http://www.hibernate.org/dtd/hibernate-mapping-3.0.dtd">
<hibernate-mapping package="cn.siggy.pojo">
	<class name="IdCard">
		<id name="id">
			<generator class="native"></generator>
		</id>
		<property name="code"/>
		<one-to-one name="person" property-ref="idCard"/>
	</class>
</hibernate-mapping>

 

Person.hbm.xml

<?xml version="1.0"?>
<!DOCTYPE hibernate-mapping PUBLIC 
	"-//Hibernate/Hibernate Mapping DTD 3.0//EN"
	"http://www.hibernate.org/dtd/hibernate-mapping-3.0.dtd">
<hibernate-mapping package="cn.siggy.pojo">
	<class name="Person">
		<id name="id">
			<generator class="native"></generator>
		</id>
		<property name="name"/>
		<property name="age"/>
		<!-- 
		unique="true"时候 可以设置一对一的关系
		 -->
		<many-to-one name="idCard" class="IdCard" cascade="save-update"
		column="idcard_id" foreign-key="fk_idcard" not-null="true" 
		unique="true"/>
	</class>
</hibernate-mapping>

　　

4.测试代码【由上至下依次单元测试@Test】

public class HibernateTest {
	@Test
	public void testCreateDB(){
		Configuration cfg = new Configuration().configure();
		SchemaExport se = new SchemaExport(cfg);
		//第一个参数 是否生成ddl脚本  第二个参数  是否执行到数据库中
		se.create(true, true);
	}
	@Test
	public void testSave() throws HibernateException, SerialException, SQLException{
		Session session = null;
		Transaction tx = null;
		try{
			session = HibernateUtil.getSession();
			tx = session.beginTransaction();
			IdCard id1 = new IdCard();
			id1.setCode("320123231212112");
			IdCard id2 = new IdCard();
			id2.setCode("110231432423432");
			Person person1 = new Person();
			person1.setName("贾宝玉");
			person1.setAge(23);
			person1.setIdCard(id1);
			Person person2 = new Person();
			person2.setName("林黛玉");
			person2.setAge(22);
			person2.setIdCard(id2);
			Person person3 = new Person();
			person3.setName("薛宝钗");
			person3.setAge(21);
			person3.setIdCard(id2);
			session.save(person1);
			session.save(person2);
			//当保存person3出错
			//session.save(person3);
			tx.commit();
			
		}catch (HibernateException e) {
			if(tx!=null)
				tx.rollback();
			e.printStackTrace();
			throw e;
		}finally{
			HibernateUtil.closeSession();
		}
	}
	@Test
	public void testGet(){
		Session session = null;
		Transaction tx = null;
		try{
			session = HibernateUtil.getSession();
			tx = session.beginTransaction();
			Person person = (Person)session.get(Person.class, 1);
			System.out.println("personName="+person.getName()+"---IdCard:"+person.getIdCard().getCode());
			System.out.println("=======================================");
			IdCard idCard = (IdCard)session.get(IdCard.class, 2);
			System.out.println("personName="+idCard.getPerson().getName()+"--Idcard:"+idCard.getCode());
			//取数据
			tx.commit();
		}catch (HibernateException e) {
			if(tx!=null)
				tx.rollback();
			e.printStackTrace();
			throw e;
		}finally{
			HibernateUtil.closeSession();
		}
	}
}

　　

5.测试结果

1.运行testSave()方法：

 

2.运行testGet()方法：