Hibernate对象映射关系：一对一

标签：hibernate

一：项目截图

二：业务代码

package com.cloud.domain;
import java.util.Date;
public class IdCard {
private Integer id;
private Date validateDte;
private Person person;
public Integer getId() {
return id;
}
public void setId(Integer id) {
this.id = id;
}
public Date getValidateDte() {
return validateDte;
}
public void setValidateDte(Date validateDte) {
this.validateDte = validateDte;
}
public Person getPerson() {
return person;
}
public void setPerson(Person person) {
this.person = person;
}
}

package com.cloud.domain;
public class Person {
private Integer id;
private String name;
private IdCard idCard;
public Integer getId() {
return id;
}
public void setId(Integer id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public IdCard getIdCard() {
return idCard;
}
public void setIdCard(IdCard idCard) {
this.idCard = idCard;
}
}

三：项目配置文件

IdCard.hbm.xml

<?xml version="1.0"encoding="utf-8"?>

<!DOCTYPE hibernate-mapping PUBLIC "-//Hibernate/HibernateMapping DTD 3.0//EN"

"http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd">

<hibernate-mapping package="com.cloud.domain">

<class name="IdCard"table="idCard">

   <!--<id name="id" type="java.lang.Integer">-->

   <!--因为这里是基于主键的one-to-one,所以要使用外键策略 -->

   <!--<generator class="foreign">-->

   <!--这里的值是指哪个属性one-to-one -->

   <!--

   <paramname="property">person</param>

   </generator>

   </id>

    -->

    <!-- 这里配置演示基于外键的one-to-one -->

    <id name="id"type="java.lang.Integer">

    <generator class="assigned"/>

    </id>

   <property name="validateDte" type="java.util.Date">

   <column name="validateDte"/>

   </property>

   <!-- 配置idcard和person一对一关系，先有一个人，才有一张身份证 -->

   <!-- 

   <one-to-onename="person"></one-to-one>

   -->

   <!-- 可以有多条数据指向同一个主键 -->

   <many-to-one name="person" unique="true"/>

</class>

</hibernate-mapping>

Person.hbm.xml

<?xml version="1.0"encoding="utf-8"?>

<!DOCTYPE hibernate-mapping PUBLIC "-//Hibernate/HibernateMapping DTD 3.0//EN"

"http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd">

<hibernate-mapping package="com.cloud.domain">

<class name="Person"table="person">

<id name="id"type="java.lang.Integer">

<!-- 这里手动分配id -->

<generator class="assigned"/>

</id>

<property name="name"type="java.lang.String">

<column name="name"length="128"/>

</property>

<!-- 配置person和idcard一对一关系，先有一个人，才有一张身份证 -->

<one-to-one name="idCard"></one-to-one>

</class>

</hibernate-mapping>

Hibernate.cfg.xml

<?xml version=‘1.0‘ encoding=‘UTF-8‘?>

<!DOCTYPE hibernate-configuration PUBLIC

          "-//Hibernate/Hibernate Configuration DTD 3.0//EN"

          "http://hibernate.sourceforge.net/hibernate-configuration-3.0.dtd">

<!-- Generated by MyEclipse HibernateTools.                   -->

<hibernate-configuration>

<session-factory>

   <property name="dialect">

      org.hibernate.dialect.MySQLDialect

   </property>

   <property name="connection.url">

      jdbc:mysql://localhost:3306/zjgm01

   </property>

   <property name="connection.username">root</property>

   <property name="connection.password">root</property>

   <property name="connection.driver_class">

      com.mysql.jdbc.Driver

   </property>

   <property name="show_sql">true</property>

   <!-- 配置hibernate自动创建关系模型表 -->

   <property name="hbm2ddl.auto">update</property>

   <mapping resource="com/cloud/domain/Person.hbm.xml" />

   <mapping resource="com/cloud/domain/IdCard.hbm.xml" />

</session-factory>

</hibernate-configuration>

package com.cloud.view;
import java.util.Date;
import org.hibernate.Session;
import org.hibernate.Transaction;
import com.cloud.domain.IdCard;
import com.cloud.domain.Person;
import com.cloud.util.HibernateUtil;
public class TestMain {
public static void main(String[] args) {
//添加一组学生和IdCard
Session s=null;
Transaction ts=null;
try {
s=HibernateUtil.getCurrentSession();
ts=s.beginTransaction();
//测试基于主键的one-to-one
/*
Person p1=new Person();
p1.setId(123);
p1.setName("朝阳");
IdCard idCard=new IdCard();
idCard.setValidateDte(new Date());
//这里表示idCard是属于p1对象的
idCard.setPerson(p1);
//必须先保存人
s.save(p1);
s.save(idCard);
*/
//基于外键测试one-to-one
Person p1=new Person();
p1.setId(11);
p1.setName("春天");
IdCard idCard=new IdCard();
idCard.setId(2015);
idCard.setValidateDte(new Date());
//这里表示idCard是属于p1对象的
idCard.setPerson(p1);
//必须先保存人
s.save(p1);
s.save(idCard);
ts.commit();
} catch (Exception e) {
if(ts!=null){
ts.rollback();
}
}finally{
if(s!=null && s.isOpen()){
s.close();
}
}
}
}

五：测试结果

Hibernate: insert into person (name, id) values (?, ?)
Hibernate: insert into idCard (validateDte, person, id) values (?, ?, ?)

Hibernate对象映射关系：一对一

标签：hibernate

原文地址：http://blog.csdn.net/dzy21/article/details/47812851