Hibernate关系映射.docx

目 录1关系映射11.1 单向关联11.1.1 一对一外键单向关联11.1.2 一对一主键单向关联41.1.3 一对多外键单向关联51.1.4 多对一外键单向关联81.2 双向关联101.2.1 一对一外键双向关联101.2.2 一对一主键双向关联121.2.3 一对多外键双向关联131.2.4 多对多双向关联15 1 关系映射1.1 单向关联1.1.1 一对一外键单向关联1、模型介绍一个人（Person）对应一个地址（Address）。2、实体（无getter和setter）Peronprivate Long oid;private String personid;private String name;private Address addressfk;Addressprivate Long oid;private String addressid;private String addressdetail;3、表模型以下是地址表表1 地址表以下是人物表，其中addressid是外键引用地址表的addressid表2 人物表4、映射文件Address.hbm.xmlPerson.hbm.xml5、测试方法public class Test public static void main(String args) Session s = HibernateUtil.getSession();try s.beginTransaction();Person p = new Person();p.setName(xuwei);p.setPersonid(200610801232);Address a = new Address();a.setAddressid(杨家冲6号);a.setAddressdetail(自贡市大安区);p.setAddressfk(a);s.save(a);s.save(p);s.getTransaction().commit(); catch (HibernateException e) e.printStackTrace();s.getTransaction().rollback(); finally s.close();6、测试结果a、s.save(a);s.save(p);正常保存b、s.save(p);s.save(a);异常发生，异常信息：not-null property references a null or transient valuec、s.save(a)能够插入，但信息不全，只插入一条记录。d、s.save(p)异常发生，异常信息：not-null property references a null or transient value 1.1.2 一对一主键单向关联1、要改的地方只有一个就是person.hbm.xmladdressfk2、测试结果a、s.save(a);s.save(p);正常保存，推荐方式，先插入父表，再插入子表b、s.save(p);s.save(a);正常保存，也是先插入父表，再插入子表c、s.save(a)能够插入，但信息不全，只插入一条记录。d、s.save(p)正常保存，而且插入两条记录。1.1.3 一对多外键单向关联1、模型介绍一个人（Person）对应多个地址（Address），比如家庭地址、公司地址。2、实体Addressprivate Long aid;private String addressid;private String addressdetail;Personprivate Long pid;private String personid;private String name;private Set addresses = new HashSet();3、表模型以下是地址表此表是多的一方pid为外键表3 地址表以下是人物表表4 人物表4、映射文件Address.hbm.xmlPerson.hbm.xml5、测试方法public class Test public static void main(String args) Session s = HibernateUtil.getSession();try s.beginTransaction();Person p = new Person();Address a1 = new Address();Address a2 = new Address();a1.setAddressid(杨家1号);a1.setAddressdetail(自贡市大安区);a2.setAddressid(杨家2号);a2.setAddressdetail(自贡市大安区);p.setName(xuwei);p.setPersonid(1);p.getAddresses().add(a1);p.getAddresses().add(a2);s.save(a1);s.save(a2);s.save(p);s.getTransaction().commit(); catch (HibernateException e) e.printStackTrace();s.getTransaction().rollback(); finally s.close();6、测试结果a、s.save(a1);s.save(a2); s.save(p);正常保存，信息：Hibernate: insert into address (addressid, addressdetail) values (?, ?)Hibernate: insert into address (addressid, addressdetail) values (?, ?)Hibernate: insert into person (personid, name) values (?, ?)Hibernate: update address set pid=? where aid=?Hibernate: update address set pid=? where aid=?b、s.save(p)正常保存，同上。c、s.save(a1);s.save(a2);正常保存，但信息不全：Hibernate: insert into address (addressid, addressdetail) values (?, ?)Hibernate: insert into address (addressid, addressdetail) values (?, ?)1.1.4 多对一外键单向关联1、模型介绍多个人（Person）对应一个地址（Address）。2、实体Addressprivate Long oid;private String addressid;private String addressdetail;Personprivate Long oid;private String personid;private String name;private Address addressfk;3、表模型以下是地址表表5 地址表以下是人物表，多个人对应一个地址：表6 人物表4、映射文件Person.hbm.xml5、测试方法Person p1 = new Person();Person p2 = new Person();Address a = new Address();p1.setName(xuwei);p1.setPersonid(001);p2.setName(weixu);p2.setPersonid(002);a.setAddressid(杨家1号);a.setAddressdetail(自贡市大安区);p1.setAddressfk(a);p2.setAddressfk(a);s.save(a);s.save(p1);s.save(p2);6、测试结果a、s.save(a); s.save(p1); s.save(p2);正常保存，信息为：Hibernate: insert into address (addressid, addressdetail) values (?, ?)Hibernate: insert into person (personid, name, addressid) values (?, ?, ?)Hibernate: insert into person (personid, name, addressid) values (?, ?, ?)b、s.save(p1); s.save(p2); s.save(a);正常保存，信息：Hibernate: insert into person (personid, name, addressid) values (?, ?, ?)Hibernate: insert into person (personid, name, addressid) values (?, ?, ?)Hibernate: insert into address (addressid, addressdetail) values (?, ?)Hibernate: update person set personid=?, name=?, addressid=? where pid=?Hibernate: update person set personid=?, name=?, addressid=? where pid=?c、s.save(p1); s.save(p2);发生异常，异常信息：Hibernate: insert into person (personid, name, addressid) values (?, ?, ?)Hibernate: insert into person (personid, name, addressid) values (?, ?, ?)org.hibernate.TransientObjectException: object references an unsaved transient instance1.2 双向关联1.2.1 一对一外键双向关联1、模型介绍同一对一单向关联2、实体Personprivate Long oid;private String name;private Address addressfk;Addressprivate Long oid;private String addressdetail;private Person personfk;3、表模型表7 address表表8 person表3、映射文件Address.hbm.xmlPerson.hbm.xml4、测试Person p = new Person();p.setName(xuwei);Address a = new Address();a.setAddressdetail(自贡市大安区);p.setAddressfk(a);a.setPersonfk(p);s.save(p);5、测试结果a、p.setAddressfk(a);a.setPersonfk(p);s.save(p);正常保存，信息如下：Hibernate: insert into person (name) values (?)Hibernate: insert into address (addressdetail, personid) values (?, ?)b、p.setAddressfk(a);a.setPersonfk(p);s.save(a);异常抛出，信息如下：not-null property references a null or transient value1.2.2 一对一主键双向关联1、需要改动的地方就是Address.hbm.xmlpersonfk1.2.3 一对多外键双向关联1、模型介绍一个人（Person）对于多个地址（Address）2、实体Addressprivate Long oid;private String addressdetail;private Person personfk;Personprivate Long oid;private String name;private Set addresses = new HashSet();3、表模型表9 address表表10 person表4、映射文件Address.hbm.xmlPerson.hbm.xml5、测试方法s.beginTransaction();Person p = new Person();Address a1 = new Address();Address a2 = new Address();a1.setAddressdetail(自贡市大安区);a2.setAddressdetail(自贡市大安区);p.setName(xuwei);p.getAddresses().add(a1);p.getAddresses().add(a2);a1.setPersonfk(p);a2.setPersonfk(p);s.save(p);s.saveOrUpdate(a1);s.saveOrUpdate(a2);s.getTransaction().commit();6、测试结果s.save(p);s.saveOrUpdate(a1);s.saveOrUpdate(a2);或者s.save(p);或者s.saveOrUpdate(a1);s.saveOrUpdate(a2);均能正常保存1.2.4 多对多双向关联1、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。2、实体Addressprivate Long oid;private String addressdetail;private Set persons=new HashSet();Personprivate Long oid;private String name;private Set addresses = new HashSet();3、表模型表11 Address表表12 Person表表13 中间关系表4、映射文件Person.hbm.xmlAddress.hbm.xml5、测试方法s.beginTransaction();Person p1= new Person();Person p2= new Person();Address a1 = new Address();Address a2 = new Address();a1.setAddressdetail(自贡市大安区);a2.setAddressdetail(内江市威远县);p1.setName(xuwei);p2.setName(weixu);p1.getAdd