內蒙古java團隊

二.雙向一對一關聯
需要對TGroup.java和TGroup.hbm.xml文件作修改

1.在TGroup.java中增加一個TUser類和相應的getter、setter方法
TGroup.java
package?cn.blogjava.start;

import?java.io.Serializable;

public?class?TGroup?implements?Serializable?{
????
????private?Integer?id;
????private?String?name;
????private?TUser?user;
????
????public?TUser?getUser()?{
????????return?user;
????}
????public?void?setUser(TUser?user)?{
????????this.user?=?user;
????}
????public?Integer?getId()?{
????????return?id;
????}
????public?void?setId(Integer?id)?{
????????this.id?=?id;
????}
????public?String?getName()?{
????????return?name;
????}
????public?void?setName(String?name)?{
????????this.name?=?name;
????}
????
}

2.在TGroup.hbm.xml中增加one-to-one配置
<?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="cn.blogjava.start.TGroup"?table="T_Group"?catalog="sample">
????????<id?name="id"?type="integer">
????????????<column?name="id"?/>
????????????<generator?class="native"?/>
????????</id>
????????<property?name="name"?type="string"?column="name"?/>
????????<one-to-one?
?????????????????????name="user"
?????????????????????class="cn.blogjava.start.TUser"
?????????????????????property-ref="group"
?????????????????????/>
????</class>
</hibernate-mapping>
</DIV>
這樣就實現了雙向關聯。可以實現雙向查詢
package?cn.blogjava.start;

import?java.util.List;

import?junit.framework.Assert;
import?junit.framework.TestCase;

import?org.hibernate.HibernateException;
import?org.hibernate.Session;
import?org.hibernate.SessionFactory;
import?org.hibernate.Transaction;
import?org.hibernate.cfg.Configuration;


public?class?HibernateTest?extends?TestCase?{
????
????Session?session?=?null;

????protected?void?setUp()?{
????????try?{
????????????Configuration?config?=?new?Configuration().configure();
????????????SessionFactory?sessionFactory?=?config.buildSessionFactory();
????????????session?=?sessionFactory.openSession();
????????????
????????}?catch?(HibernateException?e)?{
????????????e.printStackTrace();
????????}????????
????}

????protected?void?tearDown()?{
????????try?{
????????????session.close();????????
????????}?catch?(HibernateException?e)?{
????????????e.printStackTrace();
????????}????????
????}????
????
????/**
?????*?對象持久化測試(Insert方法)
?????*/????????
????public?void?testInsert()?{
????????Transaction?tran?=?null;
????????try?{
????????
????????????TUser?user?=?new?TUser();
????????????user.setName("byf");
????????????user.setAge(new?Integer(26));
????????????
????????????TGroup?group?=?new?TGroup();
????????????group.setName("Admin");
??????????????????????????????????
????????????tran?=?session.beginTransaction();????????????????????
????????????//設置關聯
????????????user.setGroup(group);

????????????session.save(user);
????????????session.flush();
????????????tran.commit();
????????????Assert.assertEquals(user.getId().intValue()>0?,true);
????????}?catch?(HibernateException?e)?{
????????????e.printStackTrace();
????????????Assert.fail(e.getMessage());
????????????if(tran?!=?null)?{
????????????????try?{
????????????????????tran.rollback();
????????????????}?catch?(Exception?e1)?{
????????????????????e1.printStackTrace();
????????????????}
????????????}
????????}
????}
????
????/**
?????*?對象讀取測試(Select方法)
?????*/????????????
????public?void?testSelect(){
????????String?hql?=?"?from?TUser?where?name='byf'";
????????String?hql2?=?"?from?TGroup?where?name='admin'";
????????try?{
????????????List?userList?=?session.createQuery(hql).list();
????????????TUser?user?=?(TUser)userList.get(0);
????????????System.out.println("user?name?is?"?+?user.getName());
????????????System.out.println("user?group?is?"?+?user.getGroup().getName());
????????????Assert.assertEquals(user.getName(),?"byf");
????????????
????????????List?groupList?=?session.createQuery(hql2).list();
????????????TGroup?group?=?(TGroup)groupList.get(0);
????????????System.out.println("group?name?is?"?+?group.getName());
????????????System.out.println("group?user?is?"?+?group.getUser().getName());
????????????Assert.assertEquals(group.getUser().getName(),?"byf");????????????
????????}?catch?(Exception?e)?{
????????????e.printStackTrace();
????????????Assert.fail(e.getMessage());
????????}
????}
}