13.Hibernate双向无链表的1-N映射

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一的一方映射文件使用one-to-many

<?xml version="1.0" encoding="GBK"?><!-- 指定Hibernate的DTD信息 --><!DOCTYPE hibernate-mapping PUBLIC "-//Hibernate/Hibernate Mapping DTD 3.0//EN""http://www.hibernate.org/dtd/hibernate-mapping-3.0.dtd"><hibernate-mapping package="org.crazyit.app.domain"><!-- 映射Person持久化类--><class name="Person" table="person_inf"><!-- 映射标识属性id --><id name="id" column="person_id"><!-- 定义主键生成器策略 --><generator class="identity"/></id><!-- 用于映射普通属性 --><property name="name" type="string"/><property name="age" type="int"/><!-- 映射集合属性，集合元素是其他持久化实体没有指定cascade属性，指定不控制关联关系 --><set name="addresses" inverse="true"><!-- 指定关联的外键列 --><key column="person_id"/><!-- 用以映射到关联类属性 --><one-to-many class="Address"/></set></class></hibernate-mapping>

多的一方

<?xml version="1.0" encoding="GBK"?><!-- 指定Hibernate的DTD信息 --><!DOCTYPE hibernate-mapping PUBLIC "-//Hibernate/Hibernate Mapping DTD 3.0//EN""http://www.hibernate.org/dtd/hibernate-mapping-3.0.dtd"><hibernate-mapping package="org.crazyit.app.domain"><!-- Address持久化类--><class name="Address" table="address_inf"><!-- 映射标识属性addressId --><id name="addressId" column="address_id"><!-- 指定主键生成器策略 --><generator class="identity"/></id><!-- 映射普通属性addressdetail --><property name="addressDetail"/><!-- 必须指定列名为person_id,与关联实体中key元素的column属性值相同 --><many-to-one name="person" class="Person"column="person_id" not-null="true"/></class></hibernate-mapping>

package org.crazyit.app.domain;public class Address{//标识属性private int addressId;//地址详细信息private String addressDetail;//记录关联实体的person属性private Person person;//无参数的构造器public Address(){}//初始化全部属性的构造器public Address(String addressDetail){this.addressDetail = addressDetail;}//addressId属性的setter和getter方法public void setAddressId(int addressId){this.addressId = addressId;}public int getAddressId(){return this.addressId;}//addressDetail属性的setter和getter方法public void setAddressDetail(String addressDetail){this.addressDetail = addressDetail;}public String getAddressDetail(){return this.addressDetail;}//person属性的setter和getter方法public void setPerson(Person person){this.person = person;}public Person getPerson(){return this.person;}}

package org.crazyit.app.domain;import java.util.*; public class Person{//标识属性private Integer id;//Person的name属性private String name;//保留Person的age属性private int age;//1－N关联关系，使用Set来保存关联实体private Set<Address> addresses= new HashSet<Address>();//id属性的setter和getter方法public void setId(Integer id){this.id = id;}public Integer getId(){return this.id;}//name属性的setter和getter方法public void setName(String name){this.name = name;}public String getName(){return this.name;}//age属性的setter和getter方法public void setAge(int age){this.age = age;}public int getAge(){return this.age;}//addresses属性的setter和getter方法public void setAddresses(Set<Address> addresses){this.addresses = addresses;}public Set<Address> getAddresses(){return this.addresses;}}

测试

public class PersonManager{public static void main(String[] args){PersonManager mgr = new PersonManager();mgr.testPerson();HibernateUtil.sessionFactory.close();}private void testPerson(){Session session = HibernateUtil.currentSession();Transaction tx = session.beginTransaction();//创建一个Person对象Person p = new Person();//设置Person的Name为Yeeku字符串p.setName("Yeeku");p.setAge(29);//持久化Person对象(对应于插入主表记录)session.save(p);//创建一个瞬态的Address对象Address a = new Address("广州天河");//先设置Person和Address之间的关联关系a.setPerson(p);//再持久化Address对象(对应于插入从表记录)session.persist(a);//创建一个瞬态的Address对象Address a2 = new Address("上海虹口");//先设置Person和Address之间的关联关系a2.setPerson(p);//再持久化Address对象(对应于插入从表记录)session.persist(a2);tx.commit();HibernateUtil.closeSession();}}

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