hibernate映射:Hibernate入门教程 Hibernate关系映射详解

　　Hibernate关系映射是1对1one-to-one

　　1对1关系在现实中很常见比方说:人和身份证1个身份证对应着个身份证个身份证对应着个人那么我们就以此为原型进行代码编写

　　建立实体模型如右:



　　根据模型创建数据库:

useHibernateQuickUse;
droptableexistsPerson;
droptableexistsCard;

createtableCard(
idvarchar(32)primarykey,
cardDescvarchar(128)notnull
);

createtablePerson(
idvarchar(32)primarykey,
namevarchar(32)notnull,
card_idvarchar(32)notnull,
foreignkey(card_id)referencesCard(id)
);

　　Java代码如下:

　　Person类

　　packageorg.py.hib.relation.one2one;

/**
*Personentity.
*/

@SuppressWarnings("serial")
publicPersonimplementsjava.io.Serializable
{
privateStringid;

privateStringname;

privateCardcard;

publicPerson
{
}

publicStringgetId
{
this.id;
}

publicvoidId(Stringid)
{
this.id=id;
}

publicCardgetCard
{
this.card;
}

publicvoidCard(Cardcard)
{
this.card=card;
}

publicStringgetName
{
this.name;
}

publicvoidName(Stringname)
{
this.name=name;
}

}

　　Card类: 　　packageorg.py.hib.relation.one2one;

/**
*Cardentity.
*/

@SuppressWarnings("serial")
publicCardimplementsjava.io.Serializable
{
privateStringid;

privateStringcardDesc;

publicCard
{
}

publicStringgetId
{
this.id;
}

publicvoidId(Stringid)
{
this.id=id;
}

publicStringgetCardDesc
{
cardDesc;
}

publicvoidCardDesc(StringcardDesc)
{
this.cardDesc=cardDesc;
}
}

　　XML映射文件如下:

　　Person.hbm.xml

　　"http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd">cascade="all"column="card_id"/>

　　今天讲是one-to-one配置但是此处用是many-to-one这个是什么原因呢？其实one-to-one就是特殊many-to-one

　　Card.hbm.xml:

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

　　测试代码如下:

　　One2OneTest.java

　　packageorg.py.hib.relation.one2one;

importjunit.framework.Assert;
importjunit.framework.TestCase;

importorg.hibernate.Session;
importorg.hibernate.SessionFactory;
importorg.hibernate.Transaction;
importorg.hibernate.cfg.Configuration;
importorg.junit.After;
importorg.junit.Before;

publicOne2OneTestextendsTestCase
{
privateSessionFactoryfactory;

privateStringm_name="ryanpoy";

privateStringm_name2="ryanpoy2";

privateStringm_cardDesc1="desc_1";

privateStringm_cardDesc2="desc_2";

@Before
publicvoidUpthrowsException
{
Configurationconf=Configuration.configure;
factory=conf.buildSessionFactory;
}

/**
*测试添加
*@throwsException
*/
publicvoidtestSavethrowsException
{
.out.prln("n=testsave=");

Cardcard=Card;
card.CardDesc(m_cardDesc1);

Personperson=Person;
person.Name(m_name);//设置用户名=m_name
person.Card(card);

Sessionsession=null;
Transactiontran=null;
try
{
session=factory.openSession;
tran=session.beginTransaction;
session.save(person);

tran.commit;

Assert.assertEquals(person.getId!=null,true);
Assert.assertEquals(card.getId!=null,true);

}catch(Exceptionex)
{
tran.rollback;
throwex;
}finally
{
(session!=null)
{
try
{
session.close;
}catch(Exceptionex)
{
//nothingtodo
}finally
{
(session!=null)
session=null;
}
}
}
}

/**
*测试查询
*@throwsException
*/
publicvoidtestFindthrowsException
{
.out.prln("n=testfind=");
Sessionsession=null;
try
{
session=factory.openSession;
Personperson=(Person)session.createQuery("fromPerson").list.get(0);

Assert.assertEquals(true,person.getId!=null);
Assert.assertEquals(m_name,person.getName);

Assert.assertEquals(true,person.getCard.getId!=null);
Assert.assertEquals(m_cardDesc1,person.getCard.getCardDesc);

}catch(Exceptionex)
{
throwex;
}finally
{
(session!=null)
{
try
{
session.close;
}catch(Exceptionex)
{
//nothingtodo
}finally
{
(session!=null)
session=null;
}
}
}
}

/**
*测试修改
*@throwsException
*/
publicvoidtestModythrowsException
{
.out.prln("n=testmody=");
Sessionsession=null;
Transactiontran=null;
try
{
session=factory.openSession;
tran=session.beginTransaction;

Personperson=(Person)session.createQuery("fromPerson").list.get(0);
person.Name(m_name2);//修改用户名=m_name2.(原来用户名=m_name)
person.getCard.CardDesc(m_cardDesc2);//修改cardDesc为m_cardDesc2(原来是:m_cardDesc1)
tran.commit;

}catch(Exceptionex)
{
throwex;
}finally
{
(session!=null)
{
try
{
session.close;
}catch(Exceptionex)
{
//nothingtodo
}finally
{
(session!=null)
session=null;
}
}
}

/*
*修改后再查询
*/
.out.prln("n=testfindaftermody=");
try
{
session=factory.openSession;
Personperson=(Person)session.createQuery("fromPerson").list.get(0);

Assert.assertEquals(true,person.getId!=null);
Assert.assertEquals(m_name2,person.getName);

Assert.assertEquals(true,person.getCard.getId!=null);
Assert.assertEquals(m_cardDesc2,person.getCard.getCardDesc);

}catch(Exceptionex)
{
throwex;
}finally
{
(session!=null)
{
try
{
session.close;
}catch(Exceptionex)
{
//nothingtodo
}finally
{
(session!=null)
session=null;
}
}
}
}

/**
*测试删除
*@throwsException
*/
publicvoidtestDeletethrowsException
{
.out.prln("n=testdelete=");
Sessionsession=null;
Transactiontran=null;
try
{
session=factory.openSession;
tran=session.beginTransaction;

Personperson=(Person)session.createQuery("fromPerson").list.get(0);
session.delete(person);
tran.commit;

}catch(Exceptionex)
{
throwex;
}finally
{
(session!=null)
{
try
{
session.close;
}catch(Exceptionex)
{
//nothingtodo
}finally
{
(session!=null)
session=null;
}
}
}

/*
*删除后再查询
*/
.out.prln("n=testfindafterdelete=");
try
{
session=factory.openSession;

Integernum=(Integer)session.createQuery("fromPerson").list.size;
Assert.assertEquals(0,num.Value);

num=(Integer)session.createQuery("fromCard").list.size;
Assert.assertEquals(0,num.Value);

}catch(Exceptionex)
{
throwex;
}finally
{
(session!=null)
{
try
{
session.close;
}catch(Exceptionex)
{
//nothingtodo
}finally
{
(session!=null)
session=null;
}
}
}
}

/**
*
*/
@After
publicvoidtearDownthrowsException
{
factory.close;
}

}



　　运行test测试成功.

　　在Hibernateone-to-one关系映射中其实还有种方式即:唯主见关联但是我直倾向于上面这种形式所以唯主见关联旧部介绍了

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