hibernate： many-to-many
publicclassUser{
privateintid;
privateStringfirstName;
privateStringlastName;
privateDatebirthday;
privateSet<Skill>skills=newHashSet<Skill>();
**********************************************************************
<?xmlversion="1.0"encoding="UTF-8"?>
<!DOCTYPEhibernate-mappingPUBLIC"-//Hibernate/HibernateMappingDTD3.0//EN""http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd">
<hibernate-mappingpackage="com.entity.User">
<classname="User"table="user">
<idname="id">
<generatorclass="native"></generator>
</id>
<propertyname="first_name"length="50"></property>
<propertyname="last_name"length="50"></property>
<propertyname="birthday"length="80"></property>
<!--配置User和skill多对多的关联关系-->
<!--
lazy:延迟加载
inverse="false":用于表示双向关联中的被动一端。inverse的值为false的一方负责维护关联关系
save-update：更新当前对象时，级联保存，更新附属对象
fetch="select":默认的表示查询抓取
-->
<setaccess="property"lazy="true"inverse="false"
cascade="save-update"name="skills"batch-size="10"fetch="select"
table="user_skill">
<keycolumn="fk_user_id"/>
<many-to-manyclass="com.entity.Skill"
column="fk_skill_id"/>
</set>
</class>
</hibernate-mapping>
************************************************************************
<?xmlversion="1.0"encoding="UTF-8"?>
<!DOCTYPEhibernate-mappingPUBLIC"-//Hibernate/HibernateMappingDTD3.0//EN""http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd">
<hibernate-mappingpackage="com.entity.Skill">
<classname="Skill"table="skill">
<idname="id">
<generatorclass="native"></generator>
</id>
<propertyname="name"length="50"></property>
<propertyname="description"length="50"></property>
<!--配置User和skill多对多的关联关系-->
<!--
lazy:延迟加载
inverse="false":用于表示双向关联中的被动一端。inverse的值为false的一方负责维护关联关系
save-update：更新当前对象时，级联保存，更新附属对象
fetch="select":默认的表示查询抓取
-->
<setaccess="property"lazy="true"inverse="false"
cascade="save-update"name="users"batch-size="10"fetch="select"
table="user_skill">
<keycolumn="fk_skill_id"/>
<many-to-manyclass="com.entity.User"
column="fk_user_id"/>
</set>
</class>
</hibernate-mapping>
****************************************************************
publicvoidsave(){
Sessionsession=HibernateSessionFactory.getSession();
session.beginTransaction();
//createSkill
Skills1=newSkill();
Skills2=newSkill();
s1.setNeme("技能");
s2.setNeme("Java");
//createteacher
Useru1=newUser();
Useru2=newUser();
u1.setFirstName("zhang");
u2.setLastName("san");
//createrelationship
s1.getUsers().add(u1);
s1.getUsers().add(u2);
u1.getSkills().add(s1);
u2.getSkills().add(s1);
/*因为主控方级联设置为save-update,如果设置为none,则下面被注释的代码需要开启，否则会报错*/
//session.save(t1);
//session.save(t2);
session.save(s1);
session.getTransaction().commit();
session.close();
}
*************************************************************
/**
*多对多主控方删除(可以删除中间表记录)
*/
publicvoidtestDelete(){
Stringid="402881ee175f04be01175f04c05d0001";
Sessionsession=HibernateSessionFactory.getSession();
session.beginTransaction();
Skillc1=(Skill)session.get(Skill.class,id);
session.delete(c1);
session.getTransaction().commit();
session.close();
}
/**
*多对多被控方删除(无法删除中间表记录)
*/
publicvoidtestDeleteByInverse(){
Stringid="402881ee175a2e7c01175a2e7ead0003";
Sessionsession=HibernateSessionFactory.getSession();
session.beginTransaction();
Usert1=(User)session.get(User.class,id);
session.delete(t1);
session.getTransaction().commit();
session.close();
}