Hibernate中，One2One映射关系的XML实现方式

忘是亡心i 2022-09-23 15:58 136阅读 0赞

1、关于实体之间One2One之间的映射实现

2、Person.java的实现

public class Person {
    	private int id;
    	private int age;
    	private String name;
    
           // one2one，持有IdCard
           private IdCard idCard;
        
           //get set
    }

3、Person.hbm.xml的配置

<?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="com.hibernate.entity">
    
    	<class name="Person" table="person">
    
    		
    		<id name="id" column="id">
    			
    			<generator class="native" />
    		</id>
    
    		
    		<property name="name" column="name"></property>
    		<property name="age" column="age"></property>
    
    		
    		
    		
    		<many-to-one name="idCard" unique="true" column="cardid"></many-to-one>
    
    		
    		
    		
    		
    
    		
    		
    		
    		
    
    	</class>
    
    </hibernate-mapping>

4、IdCard.java的实现

public class IdCard {
    	private int id;
    	private String idcardnumber;
            //get set
    }

5、IdCard.hbm.xml的实现

6、hibernate.cfg.xml的配置

6.1 将IdCard.hbm.xml和Person.hbm.xml加入hibernate.cfg.xml中

<mapping resource="com/hibernate/entity/IdCard.hbm.xml" />
    		<mapping resource="com/hibernate/entity/Person.hbm.xml" />

6..2 hibernate.cfg.xml的完整的配置文件

<!DOCTYPE hibernate-configuration PUBLIC
    	"-//Hibernate/Hibernate Configuration DTD 3.0//EN"
    	"http://www.hibernate.org/dtd/hibernate-configuration-3.0.dtd">
    
    <hibernate-configuration>
    	
    	<session-factory>
    
    		
    		<property name="hibernate.connection.driver_class">
    			com.mysql.jdbc.Driver
    		</property>
    		<property name="hibernate.connection.url">
    			jdbc:mysql:///hibernate
    		</property>
    		<property name="hibernate.connection.username">root</property>
    		<property name="hibernate.connection.password">1234</property>
    		
    		<property name="hibernate.dialect">
    			org.hibernate.dialect.MySQL5Dialect
    		</property>
    
    		
    		
    		<property name="hibernate.show_sql">true</property>
    		
    		<property name="hibernate.format_sql">true</property>
    		
    		<property name="hibernate.hbm2ddl.auto">update</property>
    
    		
    		<mapping resource="com/hibernate/entity/IdCard.hbm.xml" />
    		<mapping resource="com/hibernate/entity/Person.hbm.xml" />
    	</session-factory>
    </hibernate-configuration>

7、测试代码

public class HibernateTest {
    
    	@Test
    	public void testone2one() {
    
    		Person stu1 = new Person();
    		stu1.setAge(18);
    		stu1.setName("18");
    
    		IdCard idCard = new IdCard();
    		idCard.setIdcardnumber("1234567");
    
    		// 注册关系
    		stu1.setIdCard(idCard);
    
    		// 保存到数据库
    		IClassRoomDao roomDao = new ClassRoomDaoImpl();
    		IStudentDao studentDao = new StudentDaoImpl();
    
    		// 保存一的一方
    		roomDao.add(idCard);
    		// 保存多的一方
    		studentDao.add(stu1);
    
    	}
    
    }

8、程序运行结果截图

![20160721162830785][]

9、代码下载

[代码下载][Link 1]

[20160721162830785]: /images/20220720/1f7fdeb801514090acc9aa722e36c45d.png
[Link 1]: http://pan.baidu.com/s/1miCmzt2