Hibernate关联映射-one to one 外键双向关联.
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说明:双向一对一,是一对多的特例,只需要在多的一方设置成 unique=“true” 即可.
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Person_SX_FK_One_to_One Pojo代码:
/** * 双向一对一关联; * @author Administrator * */public class Person_SX_FK_One_to_One {private Integer id;private String name;private Integer age;private Address_SX_One_to_One addressSXOneToOne; //getter和setter方式省略.}?
Address_SX_One_to_One:
public class Address_SX_One_to_One implements Serializable{private static final long serialVersionUID = -8252905495596205673L;private Integer addressID;private String addressDetail;private Person_SX_FK_One_to_One personSXFKOneToOne; //getter和setter方式省略.}?
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下面是Hibernate配置文件:
Person_SX_FK_One_to_One.hbm.xml:
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<?xml version="1.0" encoding="utf-8"?><!DOCTYPE hibernate-mapping PUBLIC "-//Hibernate/Hibernate Mapping DTD 3.0//EN""http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd"><hibernate-mapping><class name="pack.java.model.Person_SX_FK_One_to_One" table="ZHT_PERSON_SX_FK_ONE_TO_ONE"><id name="id" column="ID"><generator column="NAME"></property><property name="age" column="AGE"></property><!-- 一对一配置，name指定person 类中的，address对象；class指定address的具体包和类。 --><one-to-one name="addressSXOneToOne" cascade="all"></one-to-one></class></hibernate-mapping>
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Address_SX_One_to_One.hbm.xml：
<?xml version="1.0" encoding="utf-8"?><!DOCTYPE hibernate-mapping PUBLIC "-//Hibernate/Hibernate Mapping DTD 3.0//EN""http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd"><hibernate-mapping><class name="pack.java.model.Address_SX_One_to_One" table="ZHT_ADDRESS_SX_FK_ONE_TO_ONE"><id column="ADDRESSID" name="addressID"><generator column="ADDRESS_DETAIL"></property><!-- 一对一的关联，是一对多的特例，只需要在多的一方，家在unique="true" 即可。 --><many-to-one name="personSXFKOneToOne" unique="true" fetch="select" cascade="all"></many-to-one></class></hibernate-mapping>
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在Hibernate.cfg.xml中配置刚刚加入的两个映射文件..
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然后,在写测试类,进行测试双向一对一关联关系。
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package pack.java.test;import org.hibernate.Session;import pack.java.hibernate.HibernateSessionFactory;import pack.java.model.Address_SX_One_to_One;import pack.java.model.Person_SX_FK_One_to_One;/** * 双向一对一外键关联， * @author ZhouHaiTao; * */public class HibernateDemoSX_OneToOne {/** * 测试方法; * @param args */public static void main(String[] args) {HibernateDemoSX_OneToOne demoSXOneToOne = new HibernateDemoSX_OneToOne();//保存;demoSXOneToOne.savePerson();//根据Person编号查询：Person对象；demoSXOneToOne.queryPersonByPersonID(1);//根据Address编号，查询出Address对象；demoSXOneToOne.queryAddressByAddressID(1);}/** * 保存Person； */private void savePerson(){Session session = HibernateSessionFactory.getSession();Person_SX_FK_One_to_One person = new Person_SX_FK_One_to_One();Address_SX_One_to_One address = new Address_SX_One_to_One();address.setAddressDetail("广东省广州市");person.setAge(23);person.setName("王五");person.setAddressSXOneToOne(address);address.setPersonSXFKOneToOne(person);session.beginTransaction().begin();//保存person;session.save(person);session.beginTransaction().commit();//关闭session;session.close();}/** * 根据Person编号，查询 Person; * @param personId */private void queryPersonByPersonID(Integer personId){Session session = HibernateSessionFactory.getSession();//查询出person;Person_SX_FK_One_to_One person = (Person_SX_FK_One_to_One) session.load(Person_SX_FK_One_to_One.class, personId);System.out.println("根据Person编号,找出Person对象,然后，通过Person关联到Address，输出Address对象信息:");//输出person对象中的信息;System.out.println(person.getId()+","+person.getName()+","+person.getAge()+","+person.getAddressSXOneToOne().getAddressDetail());}/** * 根据Address编号，查询出Address;a * @param addressID */private void queryAddressByAddressID(Integer addressID){Session session = HibernateSessionFactory.getSession();Address_SX_One_to_One addressSXOneToOne = (Address_SX_One_to_One) session.load(Address_SX_One_to_One.class, addressID);System.out.println("根据Address编号,找出Address对象,然后，通过Address关联到Person，输出Person对象信息:");System.out.println(addressSXOneToOne.getAddressID()+","+addressSXOneToOne.getAddressDetail()+","+addressSXOneToOne.getPersonSXFKOneToOne().getId()+","+addressSXOneToOne.getPersonSXFKOneToOne().getName());}}?
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下面是控制台输出结果:
根据Person编号,找出Person对象,然后，通过Person关联到Address，输出Address对象信息:
1,王五,23,广东省广州市
根据Address编号,找出Address对象,然后，通过Address关联到Person，输出Person对象信息:
1,广东省广州市,1,王五
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