Hibernate_8_Person和IdCard实例_一对一关系：基于外键-白红宇

Hibernate_8_Person和IdCard实例_一对一关系：基于外键

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发布时间：2019-06-27

本文共 5818 字，大约阅读时间需要 19 分钟。

1）建立Person类：

public class Person {	private Integer id;	private String name;	private IdCard IdCard;	public String getName() {		return name;	}	public void setName(String name) {		this.name = name;	}	public Integer getId() {		return id;	}	public void setId(Integer id) {		this.id = id;	}	public IdCard getIdCard() {		return IdCard;	}	public void setIdCard(IdCard card) {		this.IdCard = card;	}	@Override	public String toString() {		return "Person [id=" + id + ",name=" + name + "]";	}}

2）建立IdCard类：

public class IdCard {	private Integer id;	private String number;	private Person person;	public Integer getId() {		return id;	}	public void setId(Integer id) {		this.id = id;	}	public String getNumber() {		return number;	}	public void setNumber(String number) {		this.number = number;	}	public Person getPerson() {		return person;	}	public void setPerson(Person person) {		this.person = person;	}	@Override	public String toString() {		return "IdCard [id=" + id + ",number=" + number + "]";	}}

3）建立持久化类：

public class perAndIdDao {	/**	 * save方法	 */	@Test	public void testSave() {		Session session = SessionFactoryTools.getSession();		Transaction tx = null;		try {			tx = session.beginTransaction();			// ===============================================			// 新建两个Person对象			Person person1 = new Person();			person1.setName("张三");			Person person2 = new Person();			person2.setName("李四");			// 新建两个IdCard对象			IdCard idCard1 = new IdCard();			idCard1.setNumber("37292501");			IdCard idCard2 = new IdCard();			idCard2.setNumber("37292502");			// 加入关联对象			person1.setIdCard(idCard1);			person2.setIdCard(idCard2);			idCard1.setPerson(person1);			idCard2.setPerson(person2);			// 保存			session.save(person1);			session.save(person2);			session.save(idCard1);			session.save(idCard2);			// ===============================================			tx.commit();		} catch (RuntimeException e) {			if (tx != null) {				tx.rollback();			}			throw e;		} finally {			session.close();		}	}	/**	 * getById方法	 */	@Test	public void testGetById() {		Session session = SessionFactoryTools.getSession();		Transaction tx = null;		try {			tx = session.beginTransaction();			// ===============================================			// 获取person队象并打印改队象的信息和相关联的idCard信息			Person person = (Person) session.get(Person.class, 1);			System.out.println(person + ":");			System.out.println(person.getIdCard());			// 获取idCard对象并打印改队象的信息和相关联的person信息			IdCard idCard = (IdCard) session.get(IdCard.class, 2);			System.out.println(idCard + ":");			System.out.println(idCard.getPerson());			// ===============================================			tx.commit();		} catch (RuntimeException e) {			if (tx != null) {				tx.rollback();			}			throw e;		} finally {			session.close();		}	}	/**	 * 解除关联关系的方法	 */	@Test	public void testRemoveRelation() {		Session session = SessionFactoryTools.getSession();		Transaction tx = null;		try {			tx = session.beginTransaction();			// ===============================================			/**			 * 获取person对象并将其关联的IdCard设置为空 在多对一中，			 * 因为一方不具有外键管理权。所以解除外键关联是不能实现的			 * Person person = (Person) session.get(Person.class, 1);			 * person.setIdCard(null);			 */			/**			 * 获取idCard对象并将其相关联的person设置为空 在多对一中，			 * 因为多方具有外键的管理权限，所以该外键的解除是能够实现的			 */			IdCard idCard = (IdCard) session.get(IdCard.class, 1);			idCard.setPerson(null);			// ===============================================			tx.commit();		} catch (RuntimeException e) {			if (tx != null) {				tx.rollback();			}			throw e;		} finally {			session.close();		}	}	/**	 * 删除队象的方法	 */	@Test	public void testDelete() {		Session session = SessionFactoryTools.getSession();		Transaction tx = null;		try {			tx = session.beginTransaction();			// ===============================================			/**			 * 获取person对象并删除该对象			 * 在多对一中。因为一方不具有外键的管理权限。  	 			所以删除该对象是不可能实现的			 * Person person = (Person) session.get(Person.class, 1); 			 * session.delete(person);			 */						/**			 * 获取idCard对象并删除该对象			 * 在多对一中。因为多方具有外键爱你的管理权限，                         * 所以删除该对象是能够实现的			 */			IdCard idCard = (IdCard) session.get(IdCard.class, 1);			session.delete(idCard);			// ===============================================			tx.commit();		} catch (RuntimeException e) {			if (tx != null) {				tx.rollback();			}			throw e;		} finally {			session.close();		}	}}

4）Person.hbm.xml的配置：

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 package="map_3">  <class name="Person" table="person"> <id name="id" type="int" column="id"> <generator class="native" /> </id> <property name="name" type="string" column="name" length="20" /> <one-to-one name="idCard" class="IdCard" property-ref="person"> </one-to-one> </class> </hibernate-mapping>

5）IdCard.hbm.xml的配置：

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 package="map_3">  <class name="IdCard" table="idCard"> <id name="id" type="int" column="id"> <generator class="native" /> </id> <property name="number" type="string" column="number" /> <many-to-one name="person" class="Person" column="personId" unique="true"> </many-to-one> </class> </hibernate-mapping>

6) 主文件的配置：


     	
      		
       		
       
        org.hibernate.dialect.MySQLDialect
       		
       
        jdbc:mysql:///hibernate0
       		
       
        com.mysql.jdbc.Driver
       		
       
        root
       		
       
        root
       		
       		
       
        false
       		
       
        false
       		
       
        update

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