Hibernate 映射实体关联关系（二）

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本文介绍了Hibernate中多种关联关系的映射方式，包括一对一、一对多及多对多的单向与双向关联，并提供了详细的实体类定义、表结构、映射文件及测试代码。

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Hibernate关联关系映射目录
│
├─单向关联
│ ├─ 一对一外键单向关联
│ ├─ 一对一主键单向关联
│ ├─ 一对一连接表单向关联
│ ├─ 一对多外键单向关联
│ ├─ 一对多连接表单向关联
│ ├─ 多对一外键单向关联
│ ├─ 多对一连接表单向关联
│ └─ 多对多单向关联
└─双向关联
   ├─1 一对一外键双向关联
   ├─2 一对一主键双向关联
   ├─3 一对一连接表双向关联
   ├─4 一对多外键双向关联
   ├─5 一对多连接表双向关联

└─6 多对多双向关联

2-1 一对一外键双向关联

一对一外键关联是一对多外键关联的特例，只是在多的一方加了个唯一性约束。

一、模型

一个人对应一个地址。

/*==============================================================*/
/* DBMS name:      MySQL 5.0                                    */
/* Created on:     2008-12-9 0:12:54                            */
/*==============================================================*/

drop table if exists address;
drop table if exists person;
/*==============================================================*/
/* Table: address                                               */
/*==============================================================*/
create table address
(
   id                   bigint not null auto_increment comment 'ID',
   detail               varchar(120) not null comment '详细地址',
   personid             bigint comment '人的ID',
   primary key (id)
)
type = InnoDB;
alter table address comment '地址';
/*==============================================================*/
/* Table: person                                                */
/*==============================================================*/
create table person
(
   id                   bigint not null auto_increment comment 'ID',
   name                 varchar(24) not null comment '姓名',
   primary key (id)
)
type = InnoDB;
alter table person comment '人';
alter table address add constraint FK_Reference_4 foreign key (personid)
      references person (id) on delete restrict on update restrict;

二、对象模型

public class Person implements java.io.Serializable { 

  private Long id; 
  private String name; 
  private Address address;
 
public class Address implements java.io.Serializable { 
  private Long id; 
  private Person person; 
  private String detail;

三、映射文件

<?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="entity.Person" table="person"> 
    <id name="id" type="java.lang.Long"> 
      <column name="id" /> 
      <generator class="identity" /> 
    </id> 
    <property name="name" type="java.lang.String"> 
      <column name="name" length="24" not-null="true"> 
        <comment>姓名</comment> 
      </column> 
    </property> 
    <one-to-one name="address" cascade="all" /> 
  </class> 
</hibernate-mapping>

<?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="entity.Address" table="address" catalog="testdb"> 
    <id name="id" type="java.lang.Long"> 
      <column name="id" /> 
      <generator class="identity" /> 
    </id> 
    <property name="detail" type="java.lang.String"> 
      <column name="detail" length="120" not-null="true"> 
        <comment>详细地址</comment> 
      </column> 
    </property> 
    <many-to-one name="person" class="entity.Person" 
      fetch="select" unique="true"> 
      <column name="personid"> 
        <comment>人的ID</comment> 
      </column> 
    </many-to-one> 
  </class> 
</hibernate-mapping>

<?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 Hibernate Tools.                                     --> 
<hibernate-configuration> 

  <session-factory> 
    <property name="connection.username">root</property> 
    <property name="connection.url"> 
      jdbc:mysql://localhost:3306/testdb 
    </property> 
    <property name="dialect"> 
      org.hibernate.dialect.MySQLDialect 
    </property> 
    <property name="connection.password">xiaohui</property> 
    <property name="connection.driver_class"> 
      com.mysql.jdbc.Driver 
    </property> 
    <property name="show_sql">true</property> 
    <property name="format_sql">true</property> 
    <mapping resource="entity/Person.hbm.xml" /> 
    <mapping resource="entity/Address.hbm.xml" /> 

  </session-factory> 

</hibernate-configuration>

四、测试

import org.hibernate.Transaction; 

import entity.Address; 
import entity.Person; 

import utils.HibernateSessionFactory; 

public class Test { 
  public static void main(String[] args) { 
    savePerson(); 
  } 

  public static void savePerson() { 
    Person person = new Person("张三"); 
    Address address = new Address("XX街X号"); 
    person.setAddress(address); 
    address.setPerson(person); 

    Session session = HibernateSessionFactory.getSession(); 
    Transaction tx = session.beginTransaction(); 
    session.save(person); 
    tx.commit(); 
  } 
}

2-2 一对一主键双向关联

一对一主键映射在一对一映射中还算是最为常用的。

一、模型

一个人Person 对应一个地址Address。

二、数据模型和对象模型图

导出建表SQL如下：

/*==============================================================*/ 
/* DBMS name:            MySQL 5.0                                                                        */ 
/* Created on:         2008-12-8 23:05:32                                                     */ 
/*==============================================================*/ 


drop table if exists address; 

drop table if exists person; 

/*==============================================================*/ 
/* Table: address                                                                                             */ 
/*==============================================================*/ 
create table address 
( 
     id                                     bigint not null comment 'ID', 
     detail                             varchar(120) not null comment '详细地址', 
     primary key (id) 
) 
type = InnoDB; 

alter table address comment '地址'; 

/*==============================================================*/ 
/* Table: person                                                                                                */ 
/*==============================================================*/ 
create table person 
( 
     id                                     bigint not null auto_increment comment 'ID', 
     name                                 varchar(24) not null comment '姓名', 
     primary key (id) 
) 
type = InnoDB; 

alter table person comment '人'; 

alter table address add constraint FK_Reference_2 foreign key (id) 
            references person (id) on delete restrict on update restrict;

三、对象模型代码

public class Person implements java.io.Serializable { 

  private Long id; 
  private String name; 
  private Address address;
 
public class Address implements java.io.Serializable { 
  private Long id; 
  private Person person; 
  private String detail;

四、映射代码

<?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="entity.Person" table="person"> 
    <id name="id" type="java.lang.Long"> 
      <column name="id" /> 
      <generator class="identity" /> 
    </id> 
    <property name="name" type="java.lang.String"> 
      <column name="name" length="24" not-null="true"> 
        <comment>姓名</comment> 
      </column> 
    </property> 
    <!-- cascade="all"：在保存person对象的时候，级联保存person对象关联的address对象    --> 
    <one-to-one name="address" cascade="all" /> 
  </class> 
</hibernate-mapping>

<?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="entity.Address" table="address" catalog="mydb"> 
    <id name="id" type="java.lang.Long"> 
      <column name="id" /> 
      <!-- class="foreign": 一对一主键映射中，使用另外一个相关联的对象的标识符 --> 
      <generator class="foreign"> 
        <param name="property">person</param> 
      </generator> 
    </id> 
    <property name="detail" type="java.lang.String"> 
      <column name="detail" length="120" not-null="true"> 
        <comment>详细地址</comment> 
      </column> 
    </property> 
    <!-- 表示在address表存在一个外键约束，外键参考相关联的表person --> 
    <one-to-one name="person" constrained="true" /> 
  </class> 
</hibernate-mapping>

五、Hibernate配置

<?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 Hibernate Tools.                                     --> 
<hibernate-configuration> 

<session-factory> 
  <property name="connection.username">root</property> 
  <property name="connection.url"> 
    jdbc:mysql://localhost:3306/mydb 
  </property> 
  <property name="dialect"> 
    org.hibernate.dialect.MySQLDialect 
  </property> 
  <property name="connection.password">xiaohui</property> 
  <property name="connection.driver_class"> 
    com.mysql.jdbc.Driver 
  </property> 
  <property name="show_sql">true</property> 
  <property name="format_sql">true</property> 
  <mapping resource="entity/Person.hbm.xml" /> 
  <mapping resource="entity/Address.hbm.xml" /> 

</session-factory> 

</hibernate-configuration>

2-3 一对一连接表双向关联

一、模型介绍

一个人（Person）对应一个地址（Address）。

二、实体（省略getter、setter方法）

public class Person11tab_sx {
    private int personid;
    private String name;
    private int age;
    private Address11tab_sx address11tab_sx;
 
public class Address11tab_sx {
    private int addressid;
    private String addressdetail;
    private Person11tab_sx person11tab_sx;

三、表模型

mysql> desc person_11tab_sx;

+----------+--------------+------+-----+---------+----------------+

+----------+--------------+------+-----+---------+----------------+

| personid | int(11) | NO | PRI | NULL | auto_increment |

| age | int(11) | YES | | NULL | |

+----------+--------------+------+-----+---------+----------------+

mysql> desc join_11tab_sx;

+-----------+---------+------+-----+---------+-------+

+-----------+---------+------+-----+---------+-------+

| addressid | int(11) | NO | UNI | | |

| personid | int(11) | NO | PRI | | |

+-----------+---------+------+-----+---------+-------+

mysql> desc address_11tab_sx;

+---------------+--------------+------+-----+---------+----------------+

+---------------+--------------+------+-----+---------+----------------+

| addressid | int(11) | NO | PRI | NULL | auto_increment |

+---------------+--------------+------+-----+---------+----------------+

四、生成的SQL脚本

/* Formatted on 2007/08/22 17:35 (QP5 v5.50) */
CREATE TABLE `person_11tab_sx` (
  `personid` int(11) NOT NULL auto_increment,
  `name` varchar(255) default NULL,
  `age` int(11) default NULL,
  PRIMARY KEY  (`personid`)
) ENGINE=InnoDB DEFAULT CHARSET=gbk;
 
/* Formatted on 2007/08/22 17:34 (QP5 v5.50) */
CREATE TABLE `address_11tab_sx` (
  `addressid` int(11) NOT NULL auto_increment,
  `addressdetail` varchar(255) default NULL,
  PRIMARY KEY  (`addressid`)
) ENGINE=InnoDB DEFAULT CHARSET=gbk;
 
/* Formatted on 2007/08/22 18:35 (QP5 v5.50) */
CREATE TABLE `join_11tab_sx` (
  `addressid` int(11) NOT NULL,
  `personid` int(11) NOT NULL,
  PRIMARY KEY  (`personid`),
  UNIQUE KEY `addressid` (`addressid`),
  UNIQUE KEY `personid` (`personid`),
  KEY `FKF4AA80E44327AAB6` (`personid`),
  KEY `FKF4AA80E460C0C9F0` (`addressid`),
  CONSTRAINT `FKF4AA80E460C0C9F0` FOREIGN KEY (`addressid`) REFERENCES `address_11tab_sx` (`addressid`),
  CONSTRAINT `FKF4AA80E44327AAB6` FOREIGN KEY (`personid`) REFERENCES `person_11tab_sx` (`personid`)
) ENGINE=InnoDB DEFAULT CHARSET=gbk;

五、映射方法

<hibernate-mapping>
    <class name="com.lavasoft.sx._1_1_tab.Person11tab_sx" table="PERSON_11tab_sx">
        <id name="personid">
            <generator class="identity"/>
        </id>
        <property name="name"/>
        <property name="age"/>
        <join table="join_11tab_sx"
              optional="true">
            <key column="personid"
                 unique="true"/>
            <many-to-one name="address11tab_sx"
                         column="addressid"
                         not-null="true"
                         unique="true"/>
        </join>
    </class>
</hibernate-mapping>

<hibernate-mapping>
    <class name="com.lavasoft.sx._1_1_tab.Address11tab_sx" table="ADDRESS_11tab_sx">
        <id name="addressid">
            <generator class="identity"/>
        </id>
        <property name="addressdetail"/>
        <join table="join_11tab_sx"
              optional="true"
              inverse="true">
            <key column="addressid"
                 unique="true"/>
            <many-to-one name="person11tab_sx" column="personid"
                         not-null="true" unique="true"/>
        </join>
    </class>
</hibernate-mapping>

六、测试方法

public class Test_11tab_sx {
    public static void main(String[] args){
        Address11tab_sx add = new Address11tab_sx();
        Person11tab_sx p = new Person11tab_sx();
 
        add.setAddressdetail("郑州市经三路");
        p.setAge(12);
        p.setName("wudalang");
 
        add.setPerson11tab_sx(p);
        p.setAddress11tab_sx(add);
 
        Session session = HibernateUtil.getCurrentSession();
        Transaction tx = session.beginTransaction();
        session.saveOrUpdate(p);
        session.saveOrUpdate(add);
        tx.commit();
        HibernateUtil.closeSession();
    }
}

2-4 一对多外键双向关联

一、模型介绍

一个人（Person）对应多个地址（Address）。

二、实体（省略getter、setter方法）

public class Person1nfk_sx implements Serializable {
    private int personid;
    private String name;
    private int age;
    private Set addresses=new HashSet();
 
public class Address1nfk_sx implements Serializable {
    private int addressid;
    private String addressdetail;
    private Person1nfk_sx person1nfkSx;

三、表模型

mysql> desc person_1nfk_sx;

+----------+--------------+------+-----+---------+----------------+

+----------+--------------+------+-----+---------+----------------+

| personid | int(11) | NO | PRI | NULL | auto_increment |

| age | int(11) | YES | | NULL | |

+----------+--------------+------+-----+---------+----------------+

mysql> desc address_1nfk_sx;

+---------------+--------------+------+-----+---------+----------------+

+---------------+--------------+------+-----+---------+----------------+

| addressid | int(11) | NO | PRI | NULL | auto_increment |

| personid | int(11) | NO | MUL | | |

+---------------+--------------+------+-----+---------+----------------+

四、生成的SQL脚本

 /* Formatted on 2007/08/22 17:42 (QP5 v5.50) */
  CREATE TABLE `address_1nfk` (
    `addressid` int(11) NOT NULL auto_increment,
    `addressdetail` varchar(255) default NULL,
    `personid` int(11) default NULL,
    PRIMARY KEY  (`addressid`),
    KEY `FK9B93456DA6D6C1F5` (`personid`),
    CONSTRAINT `FK9B93456DA6D6C1F5` FOREIGN KEY (`personid`) REFERENCES `person_1nfk` (`personid`)
  ) ENGINE=InnoDB DEFAULT CHARSET=gbk;
 
 
  /* Formatted on 2007/08/22 17:42 (QP5 v5.50) */
  CREATE TABLE `person_1nfk` (
    `personid` int(11) NOT NULL auto_increment,
    `name` varchar(255) default NULL,
    `age` int(11) default NULL,
    PRIMARY KEY  (`personid`)
  ) ENGINE=InnoDB DEFAULT CHARSET=gbk;

五、映射方法

<hibernate-mapping>
    <class name="com.lavasoft.sx._1_n_fk.Person1nfk_sx" table="PERSON_1nfk_sx">
        <id name="personid">
            <generator class="identity"/>
        </id>
        <property name="name"/>
        <property name="age"/>
        <!--映射集合属性，关联到持久化类-->
        <set name="addresses" inverse="true" cascade="all">
            <!--column用于指定外键列名-->
            <key column="personid" not-null="true"/>
            <!--映射关联类-->
            <one-to-many class="com.lavasoft.sx._1_n_fk.Address1nfk_sx"/>
        </set>
    </class>
</hibernate-mapping>

<hibernate-mapping>
    <class name="com.lavasoft.sx._1_n_fk.Address1nfk_sx" table="ADDRESS_1nfk_sx">
        <id name="addressid">
            <generator class="identity"/>
        </id>
        <property name="addressdetail"/>
        <!--映射关联属性，column属性指定外键列名-->
        <many-to-one name="person1nfk"
                     class="com.lavasoft.sx._1_n_fk.Person1nfk_sx"
                     fetch="select"
                     cascade="save-update">
            <column name="personid" not-null="true"/>
        </many-to-one>
    </class>
</hibernate-mapping>

六、测试方法

public class Test_1nfk_sx {
    public static void main(String[] args){
        Address1nfk_sx add1=new Address1nfk_sx();
        Address1nfk_sx add2=new Address1nfk_sx();
        Person1nfk_sx p=new Person1nfk_sx();
 
        add1.setAddressdetail("郑州市经三路");
        add2.setAddressdetail("合肥市宿州路");
        p.setName("wang");
        p.setAge(30);
 
        p.getAddresses().add(add1);
        p.getAddresses().add(add2);
        add1.setPerson1nfk(p);
        add2.setPerson1nfk(p);
 
        Session session= HibernateUtil.getCurrentSession();
        Transaction tx=session.beginTransaction();
        session.save(p);
        session.saveOrUpdate(add1);
        session.saveOrUpdate(add2);
        tx.commit();
        HibernateUtil.closeSession();
    }
}

2-5 一对多连接表双向关联

一、模型介绍

一个人（Person）对应多个地址（Address）。

二、实体（省略getter、setter方法）

public class Person1ntab_sx {
    private int personid;
    private String name;
    private int age;
    private Set addresses=new HashSet();
 
public class Address1ntab_sx {
    private int addressid;
    private String addressdetail;
    private Person1ntab_sx person1ntab_sx;

三、表模型

mysql> desc person_1ntab_sx;

+----------+--------------+------+-----+---------+----------------+

+----------+--------------+------+-----+---------+----------------+

| personid | int(11) | NO | PRI | NULL | auto_increment |

| age | int(11) | YES | | NULL | |

+----------+--------------+------+-----+---------+----------------+

mysql> desc address_1ntab_sx;

+---------------+--------------+------+-----+---------+----------------+

+---------------+--------------+------+-----+---------+----------------+

| addressid | int(11) | NO | PRI | NULL | auto_increment |

+---------------+--------------+------+-----+---------+----------------+

mysql> desc join_1ntab_sx;

+-----------+---------+------+-----+---------+-------+

+-----------+---------+------+-----+---------+-------+

| addressid | int(11) | NO | PRI | | |

| personid | int(11) | NO | PRI | | |

+-----------+---------+------+-----+---------+-------+

四、生成的SQL脚本

/* Formatted on 2007/08/22 17:52 (QP5 v5.50) */
CREATE TABLE `address_1ntab_sx` (
  `addressid` int(11) NOT NULL auto_increment,
  `addressdetail` varchar(255) default NULL,
  PRIMARY KEY  (`addressid`)
) ENGINE=InnoDB DEFAULT CHARSET=gbk;
 
/* Formatted on 2007/08/22 17:52 (QP5 v5.50) */
CREATE TABLE `person_1ntab_sx` (
  `personid` int(11) NOT NULL auto_increment,
  `name` varchar(255) default NULL,
  `age` int(11) default NULL,
  PRIMARY KEY  (`personid`)
) ENGINE=InnoDB DEFAULT CHARSET=gbk;
 
/* Formatted on 2007/08/22 17:52 (QP5 v5.50) */
CREATE TABLE `join_1ntab_sx` (
  `addressid` int(11) NOT NULL,
  `personid` int(11) NOT NULL,
  PRIMARY KEY  (`personid`,`addressid`),
  KEY `FK8F869F61F93DDD6` (`personid`),
  KEY `FK8F869F61FC0F682A` (`addressid`),
  CONSTRAINT `FK8F869F61FC0F682A` FOREIGN KEY (`addressid`) REFERENCES `address_1ntab_sx` (`addressid`),
  CONSTRAINT `FK8F869F61F93DDD6` FOREIGN KEY (`personid`) REFERENCES `person_1ntab_sx` (`personid`)
) ENGINE=InnoDB DEFAULT CHARSET=gbk;

五、映射方法

<hibernate-mapping>
    <class name="com.lavasoft.sx._1_n_tab.Person1ntab_sx" table="PERSON_1ntab_sx">
        <id name="personid">
            <generator class="identity"/>
        </id>
        <property name="name"/>
        <property name="age"/>
        <!--映射集合属性，关联到持久化类-->
        <!--table="join_1ntab_sx"指定了连接表的名字-->
        <set name="addresses"
             table="join_1ntab_sx"
             cascade="all">
            <!--column="personid"指定连接表中关联当前实体类的列名-->
            <key column="personid" not-null="true"/>
            <!--unique="true"表示当前实体类是"1",不是"n"-->
            <many-to-many column="addressid"
                          unique="true"
                          class="com.lavasoft.sx._1_n_tab.Address1ntab_sx"/>
        </set>
    </class>
</hibernate-mapping>

<hibernate-mapping>
    <class name="com.lavasoft.sx._1_n_tab.Address1ntab_sx"
           table="ADDRESS_1ntab_sx">
        <id name="addressid">
            <generator class="identity"/>
        </id>
        <property name="addressdetail"/>
        <!--映射关联属性，column属性指定外键列名-->
        <join   table="join_1ntab_sx"
                inverse="true"
              optional="true">
            <key column="addressid"/>
            <many-to-one name="person1ntab_sx"
                         column="personid"
                         cascade="all"
                         not-null="true"/>
        </join>
    </class>
</hibernate-mapping>

六、测试方法

public class Test_1ntab_sx {
    public static void main(String[] args){
        Address1ntab_sx add1=new Address1ntab_sx();
        Address1ntab_sx add2=new Address1ntab_sx();
        Person1ntab_sx p=new Person1ntab_sx();
 
        add1.setAddressdetail("郑州市经三路");
        add2.setAddressdetail("合肥市宿州路");
        p.setName("wang");
        p.setAge(30);
 
        p.getAddresses().add(add1);
        p.getAddresses().add(add2);
        add1.setPerson1ntab_sx(p);
        add2.setPerson1ntab_sx(p);
 
        Session session= HibernateUtil.getCurrentSession();
        Transaction tx=session.beginTransaction();
//        session.save(p);
        session.saveOrUpdate(add1);
        session.saveOrUpdate(add2);
        tx.commit();
        HibernateUtil.closeSession();
    }
}

2-6 多对多双向关联

一、模型介绍

多个人（Person）对应多个地址（Address）。

一个人可对应多个地址，一个地址也可以对应多个人。

二、实体（省略getter、setter方法）

public class Personnn_sx {
    private int personid;
    private String name;
    private int age;
    private Set addresses=new HashSet();
 
public class Addressnn_sx {
    private int addressid;
    private String addressdetail;
    private Set persons = new HashSet();

三、表模型

mysql> desc person_nn_sx;

+----------+--------------+------+-----+---------+----------------+

+----------+--------------+------+-----+---------+----------------+

| personid | int(11) | NO | PRI | NULL | auto_increment |

| age | int(11) | YES | | NULL | |

+----------+--------------+------+-----+---------+----------------+

mysql> desc address_nn_sx;

+---------------+--------------+------+-----+---------+----------------+

+---------------+--------------+------+-----+---------+----------------+

| addressid | int(11) | NO | PRI | NULL | auto_increment |

+---------------+--------------+------+-----+---------+----------------+

mysql> desc join_nn_sx;

+-----------+---------+------+-----+---------+-------+

+-----------+---------+------+-----+---------+-------+

| addressid | int(11) | NO | PRI | | |

| personid | int(11) | NO | PRI | | |

+-----------+---------+------+-----+---------+-------+

四、生成的SQL脚本

/* Formatted on 2007/08/22 17:59 (QP5 v5.50) */
CREATE TABLE `address_nn_sx` (
  `addressid` int(11) NOT NULL auto_increment,
  `addressdetail` varchar(255) default NULL,
  PRIMARY KEY  (`addressid`)
) ENGINE=InnoDB DEFAULT CHARSET=gbk;
 
/* Formatted on 2007/08/22 17:59 (QP5 v5.50) */
CREATE TABLE `person_nn_sx` (
  `personid` int(11) NOT NULL auto_increment,
  `name` varchar(255) default NULL,
  `age` int(11) default NULL,
  PRIMARY KEY  (`personid`)
) ENGINE=InnoDB DEFAULT CHARSET=gbk;
 
/* Formatted on 2007/08/22 17:59 (QP5 v5.50) */
CREATE TABLE `join_nn_sx` (
  `addressid` int(11) NOT NULL,
  `personid` int(11) NOT NULL,
  PRIMARY KEY  (`personid`,`addressid`),
  KEY `FK6EBBC5EF6C600921` (`personid`),
  KEY `FK6EBBC5EF2A92FF3D` (`addressid`),
  CONSTRAINT `FK6EBBC5EF2A92FF3D` FOREIGN KEY (`addressid`) REFERENCES `address_nn_sx` (`addressid`),
  CONSTRAINT `FK6EBBC5EF6C600921` FOREIGN KEY (`personid`) REFERENCES `person_nn_sx` (`personid`)
) ENGINE=InnoDB DEFAULT CHARSET=gbk;

五、映射方法

<hibernate-mapping>
    <class name="com.lavasoft.sx._n_n.Personnn_sx" table="PERSON_nn_sx">
        <id name="personid">
            <generator class="identity"/>
        </id>
        <property name="name"/>
        <property name="age"/>
        <!--映射集合属性，关联到持久化类-->
        <!--table="join_1ntab_sx"指定了连接表的名字-->
        <set name="addresses"
             table="join_nn_sx"
             cascade="all">
            <!--column="personid"指定连接表中关联当前实体类的列名-->
            <key column="personid" not-null="true"/>
            <!--column="addressid"是连接表中关联本实体的外键-->
            <many-to-many column="addressid"
                          class="com.lavasoft.sx._n_n.Addressnn_sx"/>
        </set>
    </class>
</hibernate-mapping>

<hibernate-mapping>
    <class name="com.lavasoft.sx._n_n.Addressnn_sx"
           table="ADDRESS_nn_sx">
        <id name="addressid">
            <generator class="identity"/>
        </id>
        <property name="addressdetail"/>
        <!--table="join_nn_sx"是双向多对多的连接表-->
        <set name="persons"
             inverse="true"
             table="join_nn_sx">
            <!--column="addressid"是连接表中关联本实体的外键-->
            <key column="addressid"/>
            <many-to-many column="personid"
                          class="com.lavasoft.sx._n_n.Personnn_sx"/>
        </set>
    </class>
</hibernate-mapping>

六、测试方法

public class Test_nn_sx {
    public static void main(String[] args){
        Addressnn_sx add1=new Addressnn_sx();
        Addressnn_sx add2=new Addressnn_sx();
        Personnn_sx p1=new Personnn_sx();
        Personnn_sx p2=new Personnn_sx();
 
        add1.setAddressdetail("郑州市经三路");
        add2.setAddressdetail("合肥市宿州路");
        p1.setName("wang");
        p1.setAge(30);
        p2.setName("zhang");
        p2.setAge(22);
 
        p1.getAddresses().add(add1);
        p1.getAddresses().add(add2);
        p2.getAddresses().add(add2);
        add1.getPersons().add(p1);
        add2.getPersons().add(p1);
        add2.getPersons().add(p2);
 
 
        Session session= HibernateUtil.getCurrentSession();
        Transaction tx=session.beginTransaction();
        session.save(p1);
        session.save(p2);
//        session.saveOrUpdate(add1);
//        session.saveOrUpdate(add2);
        tx.commit();
        HibernateUtil.closeSession();
    }
}