标签:脚本 hibernate image commit 参数 pack imp java 数据库表
这篇讲解 基于外键的双向一对一关联映射
1.考察如下信息,人和身份证之间是一个一对一的关系。表的设计
2.类结构
Person.java
public class Person implements Serializable{ private int id; private String name; private IdCard idCard; public Person() { } public Person(String name) { super(); this.name = name; } public int getId() { return id; } public void setId(int id) { this.id = id; } public String getName() { return name; } public void setName(String name) { this.name = name; } public IdCard getIdCard() { return idCard; } public void setIdCard(IdCard idCard) { this.idCard = idCard; } }
IdCard.java
public class IdCard implements Serializable{ private String id; private String address; private Person person; public IdCard() { // TODO Auto-generated constructor stub } public IdCard(String id, String address) { super(); this.id = id; this.address = address; } public String getId() { return id; } public void setId(String id) { this.id = id; } public String getAddress() { return address; } public void setAddress(String address) { this.address = address; } public Person getPerson() { return person; } public void setPerson(Person person) { this.person = person; } }
3.映射文件
Person.hbm.xml
<hibernate-mapping package="cn.sxt.pojo"> <class name="Person" table="t_person"> <id name="id"> <generator class="native"></generator> </id> <property name="name"/> <!-- 基于外键的一对一和多对一的表结构是一样的,所以映射文件也一样,要保证外键是唯一的 --> <many-to-one name="idCard" column="idCardId" unique="true"></many-to-one> </class> </hibernate-mapping>
IdCard.hbm.xml
<hibernate-mapping package="cn.sxt.pojo"> <class name="IdCard" table="t_idCard"> <id name="id"> <generator class="assigned"></generator> </id> <property name="address"/> <!-- 一对一的双向关联 person表示IdCard类中属性 property-ref引用的是 person类中IdCard的属性名 --> <one-to-one name="person" property-ref="idCard"></one-to-one> </class> </hibernate-mapping>
4.测试
public class HibernateTest { /** * 生成数据库表的工具方法 * */ @Test public void testCreateDB(){ Configuration cfg = new Configuration().configure(); SchemaExport se = new SchemaExport(cfg); //第一个参数 是否打印sql脚本 //第二个参数 是否将脚本导出到数据库中执行 se.create(true, true); } /** * 初始化表数据 */ @Test public void testInit(){ Session session = null; Transaction tx = null; try { session = HibernateUtil.getSession(); tx = session.beginTransaction(); IdCard card1 = new IdCard("110086", "湖北武当"); IdCard card2 = new IdCard("110087", "光明顶"); Person p1 = new Person("张三疯"); p1.setIdCard(card1); Person p2 = new Person("殷素素"); p2.setIdCard(card2); session.save(card1); session.save(card2); session.save(p1); session.save(p2); tx.commit(); } catch (Exception e) { if(tx!=null) tx.rollback(); }finally { HibernateUtil.close(); } } /** */ @Test public void testGetData(){ Session session = HibernateUtil.getSession(); Person p1 = (Person)session.get(Person.class, 1); System.out.println(p1.getName()+"----"+p1.getIdCard().getId()+"----"+p1.getIdCard().getAddress()); System.out.println("-------------------------------------------"); IdCard card = (IdCard)session.get(IdCard.class, "110086"); System.out.println(card.getId()+"------"+card.getAddress()+"----"+card.getPerson().getName()); HibernateUtil.close(); } }
标签:脚本 hibernate image commit 参数 pack imp java 数据库表
原文地址:https://www.cnblogs.com/Vincent-yuan/p/11203321.html