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package cc.www.hibernatedemo.model;

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

  public int getId() {
    return id;
  }

  public void setId(int id) {
    this.id = id;
  }

  public String getIdCardNo() {
    return idCardNo;
  }

  public void setIdCardNo(String idCardNo) {
    this.idCardNo = idCardNo;
  }

  public Person getPerson() {
    return person;
  }

  public void setPerson(Person person) {
    this.person = person;
  }

  public IdCard() {
    // TODO Auto-generated constructor stub
  }

  @Override
  public String toString() {
    return "IdCard [id=" + id + ", idCardNo=" + idCardNo + "]";
  }

}

Person

package cc.www.hibernatedemo.model;

public class Person {
  private int id;
  private String name;
  private IdCard idCard;

  public int getId() {
    return id;
  }

  public void setId(int 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;
  }

  public Person() {
    // TODO Auto-generated constructor stub
  }

  @Override
  public String toString() {
    return "Person [id=" + id + ", name=" + name + ", idCard=" + idCard + "]";
  }

}

IdCard.hbm.xml

<?xml version="1.0"?>
<!DOCTYPE hibernate-mapping PUBLIC "-//Hibernate/Hibernate Mapping DTD 3.0//EN"
"http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd">
<hibernate-mapping>
    <class name="cc.www.hibernatedemo.model.IdCard" table="t_idcard">
        <id name="id" type="int">
            <column name="id" />
            <generator class="native" />
        </id>
        <property name="idCardNo" type="java.lang.String">
            <column name="id_cardno" />
        </property>
        <!-- property-ref="idCard" 表示和person idCard做联合查询-->
        <one-to-one name="person" class="cc.www.hibernatedemo.model.Person" property-ref="idCard"></one-to-one>
    </class>
</hibernate-mapping>

Person.hbm.xml

<?xml version="1.0"?>
<!DOCTYPE hibernate-mapping PUBLIC "-//Hibernate/Hibernate Mapping DTD 3.0//EN"
"http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd">
<!-- Generated 2019-12-29 17:20:33 by Hibernate Tools 3.5.0.Final -->
<hibernate-mapping>
    <class name="cc.www.hibernatedemo.model.Person" table="t_person">
        <id name="id" type="int">
            <column name="id" />
          <generator class="foreign">
          <!-- 关联主键 -->
            <param name="property">idCard</param>
          </generator>
        </id>
        <property name="name" type="java.lang.String">
            <column name="name" />
        </property>
        <!-- constrained="true" 表示主键ID当做外键的功能 -->
        <one-to-one name="idCard" class="cc.www.hibernatedemo.model.IdCard" constrained="true"></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://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://127.0.0.1:3306/hibernateproject?characterEncoding=utf8&amp;amp;useSSL=false</property>
  <property name="hibernate.connection.username">root</property>
  <property name="hibernate.connection.password">12345</property>
  <property name="hibernate.dialect">org.hibernate.dialect.MySQL5InnoDBDialect</property>
  <property name="hibernate.show_sql">true</property>
  <property name="hibernate.format_sql">true</property>
  <!-- 选择使用C3P0连接池 -->
  <property name="hibernate.connection.provider_class">org.hibernate.c3p0.internal.C3P0ConnectionProvider</property>
  <!-- 最大连接数 -->
  <property name="hibernate.c3p0.max_size">20</property>
  <!-- 最小连接数 -->
  <property name="hibernate.c3p0.min_size">5</property>
  <!-- 获得连接的超时时间,如果超过这个时间,会抛出异常，单位毫秒 -->
  <property name="hibernate.c3p0.timeout">120</property>
  <!-- 最大的PreparedStatement的数量 -->
  <property name="hibernate.c3p0.max_statements">100</property>
  <!-- 每隔120秒检查连接池里的空闲连接 ，单位是秒 -->
  <property name="hibernate.c3p0.idle_test_period">120</property>
  <!-- 当连接池里面的连接用完的时候，C3P0一下获取的新的连接数 -->
  <property name="hibernate.c3p0.acquire_increment">2</property>
  <property name="hibernate.hbm2ddl.auto">update</property>
  
  <mapping resource="cc/www/hibernatedemo/model/Person.hbm.xml"/>
  <mapping resource="cc/www/hibernatedemo/model/IdCard.hbm.xml"/>
 </session-factory>
</hibernate-configuration>

test()

package cc.www.hibernatedemo.model;
import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.hibernate.Transaction;
import org.hibernate.cfg.Configuration;
import org.junit.After;
import org.junit.Before;
import org.junit.Test;

import com.mysql.fabric.xmlrpc.base.Array;

import java.util.Arrays;
import java.util.Date;
import java.util.HashSet;
import java.util.Set;

@SuppressWarnings("unused")
public class StudentEntityTest {
    private SessionFactory sessionFactory=null;
    private Session session =null;
    private Transaction transaction =null;
    
    @Before
    public void init(){
      //测试同步21
        //System.out.println("开始测试文件");
        //返回的configureation,包含有配置文件里的具体信息
      
        Configuration configure = new Configuration().configure();
        //创建一个SessionFactory工厂类,通过它建立一个数据库连接会话,Session
        sessionFactory= configure.buildSessionFactory();
        
        //通过工厂类开启Session对
        session = sessionFactory.openSession();
        //开始事务
        transaction = session.beginTransaction();
    }
    
    
    @After
    public void destroy(){
        //System.out.println("结束");
        //提交事务
        transaction.commit();
        //关闭
        session.close();
        //关闭工厂
        sessionFactory.close();
    }
    
    
    @Test
    public void test() {
        //增加
        //执行数据库操作，用面向对象方式来操作数据库
      

        //增
//      IdCard idCard=new IdCard();
//      idCard.setIdCardNo("123465789");
//      
//      Person person =new Person();
//      person.setName("张三");
//      person.setIdCard(idCard);
//      
//      idCard.setPerson(person);
//      
//      
//      session.save(idCard);
//      session.save(person);
      


//      查
//      Person person = session.get(Person.class, 1);
//      System.out.println(person.getIdCard().getIdCardNo());  //报错
      
      IdCard idCard = session.get(IdCard.class, 1);
      System.out.println(idCard.getPerson());  

        //打印Person [id=1, name=张三, idCard=IdCard [id=1, idCardNo=123465789]]

      
    }
}

2.外键约束

注: 只需要修改Person.hbm.xml

<?xml version="1.0"?>
<!DOCTYPE hibernate-mapping PUBLIC "-//Hibernate/Hibernate Mapping DTD 3.0//EN"
"http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd">
<!-- Generated 2019-12-29 17:20:33 by Hibernate Tools 3.5.0.Final -->
<hibernate-mapping>
    <class name="cc.www.hibernatedemo.model.Person" table="t_person">
        <id name="id" type="int">
            <column name="id" />
      <generator class="native"></generator>
        </id>
        <property name="name" type="java.lang.String">
            <column name="name" />
        </property>
        <many-to-one name="idCard" class="cc.www.hibernatedemo.model.IdCard">
          <column name="idCard" unique="true"></column>
        </many-to-one>
    </class>
</hibernate-mapping>

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