Java进阶知识07 Hibernate一对一双向外键关联（Annotation+XML实现）

2021-06-28 02:05:37

1、Annotation 注解版

1.1、创建Husband类和Wife类

 package com.shore.model;

 import javax.persistence.Entity;

 import javax.persistence.GeneratedValue;

 import javax.persistence.GenerationType;

 import javax.persistence.Id;

 import javax.persistence.OneToOne;

 import org.hibernate.annotations.Type;

 /**

  * @author DSHORE/2019-9-18

  * 一对一，双向关联（注解版）

  */

 @Entity

 public class Husband {//主表 类

     private Integer id;

     private String name;

     private Boolean sex;

     private Wife wife;

     @Id

     @GeneratedValue(strategy = GenerationType.AUTO) //主键生成策略(使用test()测试时，必须加上这个，否会报错：id生成错误)

     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;

     }

     @Type(type = "yes_no") //数据库中，会以Y/N的形式插入到sex字段中

     public Boolean getSex() {

         return sex;

     }

     public void setSex(Boolean sex) {

         this.sex = sex;

     }

     @OneToOne(mappedBy="husband")//映射：从表wife映射主表husband。如果不要(mappedBy="husband")，主表husband将会多一个没必要的字段wife_id（外键）

     public Wife getWife() {

         return wife;

     }

     public void setWife(Wife wife) {

         this.wife = wife;

     }

 }

Wife类

 package com.shore.model;

 import javax.persistence.Entity;

 import javax.persistence.GeneratedValue;

 import javax.persistence.GenerationType;

 import javax.persistence.Id;

 import javax.persistence.JoinColumn;

 import javax.persistence.OneToOne;

 import org.hibernate.annotations.Type;

 /**

  * @author DSHORE/2019-9-18

  * 一对一，双向关联（注解版）

  */

 @Entity

 public class Wife {//从表

     private Integer id;

     private String name;

     private Boolean sex;

     private Husband husband;

     @Id

     @GeneratedValue(strategy = GenerationType.AUTO) //主键生成策略(使用test1测试时，必须加上这个，否会报错：id生成错误)

     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;

     }

     @Type(type = "yes_no") //数据库中，会以Y/N的形式插入到sex字段中

     public Boolean getSex() {

         return sex;

     }

     public void setSex(Boolean sex) {

         this.sex = sex;

     }

     @OneToOne  //默认创建的外键名称：husband_id

     @JoinColumn(name="husbandId") //创建表时，指定该外键名：husbandId

     public Husband getHusband() {

         return husband;

     }

     public void setHusband(Husband husband) {

         this.husband = husband;

     }

 }

1.2、创建hibernate.cfg.xml核心配置文件

 <?xml version='1.0' encoding='utf-8'?>

 <!DOCTYPE hibernate-configuration PUBLIC

         "-//Hibernate/Hibernate Configuration DTD 3.0//EN"

         "http://www.hibernate.org/dtd/hibernate-configuration-3.0.dtd">

 <hibernate-configuration>

     <session-factory>

         <!-- Database connection settings -->

         <property name="connection.driver_class">com.mysql.jdbc.Driver</property>

         <property name="connection.url">jdbc:mysql://localhost:3306/hibernate</property>

         <property name="connection.username">root</property>

         <property name="connection.password">123456</property>

         <property name="dialect">org.hibernate.dialect.MySQLDialect</property>

         <property name="cache.provider_class">org.hibernate.cache.NoCacheProvider</property>

         <property name="show_sql">true</property>

         <property name="hbm2ddl.auto">create</property>

         <mapping class="com.shore.model.Husband" />

         <mapping class="com.shore.model.Wife" />

     </session-factory>

 </hibernate-configuration>

1.3、开始测试

 package com.shore.test;

 import org.hibernate.Session;

 import org.hibernate.SessionFactory;

 import org.hibernate.Transaction;

 import org.hibernate.cfg.AnnotationConfiguration;

 import org.junit.AfterClass;

 import org.junit.BeforeClass;

 import org.junit.Test;

 import com.shore.model.Husband;

 import com.shore.model.Wife;

 /**

  * @author DSHORE/2019-9-18

  *

  */

 public class AnnotationTest {

     public static SessionFactory sessionFactory = null;

     public static Session session = null;

     @BeforeClass

     public static void buildSessionFactory() {

         sessionFactory = new AnnotationConfiguration().configure().buildSessionFactory();

     }

     @AfterClass

     public static void close() {

         session.close();

         sessionFactory.close();

     }

     @Test

     public void test(){//数据库表创建完后，插入数据

         session = sessionFactory.openSession(); //打开一个session

         Transaction transaction = session.beginTransaction(); //开启一个事务

         Husband husband = new Husband();

         husband.setName("黄晓明");

         husband.setSex(true);//男

         session.save(husband);

         Wife wife = new Wife();

         wife.setName("AnglaBaby");

         wife.setSex(false);//女

         wife.setHusband(husband);

         session.save(wife);

         transaction.commit(); //事务提交

     }

 }

测试结果图：

2、XML实现版

2.1、创建husband类和wife类

 package com.shore.model;

 /**

  * @author DSHORE/2019-9-18

  * 一对一，双向关联（xml版）

  */

 public class Husband {//主表 类

     private Integer id;

     private String name;

     private Boolean sex;

     private Wife wife;

     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;

     }

     public Boolean getSex() {

         return sex;

     }

     public void setSex(Boolean sex) {

         this.sex = sex;

     }

     public Wife getWife() {

         return wife;

     }

     public void setWife(Wife wife) {

         this.wife = wife;

     }

 }

wife类

 package com.shore.model;

 /**

  * @author DSHORE/2019-9-18

  * 一对一，双向关联（xml版）

  */

 public class Wife {//从表 类

     private Integer id;

     private String name;

     private Boolean sex;

     private Husband husband;

     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;

     }

     public Boolean getSex() {

         return sex;

     }

     public void setSex(Boolean sex) {

         this.sex = sex;

     }

     public Husband getHusband() {

         return husband;

     }

     public void setHusband(Husband husband) {

         this.husband = husband;

     }

 }

2.2、创建 Husband.hbm.xml 配置文件和 Wife.hbm.xml 配置文件

 <?xml version="1.0"?>

 <!DOCTYPE hibernate-mapping PUBLIC

         "-//Hibernate/Hibernate Mapping DTD 3.0//EN"

         "http://www.hibernate.org/dtd/hibernate-mapping-3.0.dtd">

 <hibernate-mapping package="com.shore.model">

     <class name="Husband" table="husband_xml">

         <id name="id">

             <generator class="native"/>

         </id>

         <property name="name" type="java.lang.String"/>

         <property name="sex" type="yes_no"/>

        <!-- 这里不能这么配置，否则主表husband里面会多一个没必要的外键wife_id

         <many-to-one name="wife" column="wife_id" unique="true"/> -->

         <!-- 应该这样配置 -->

         <one-to-one name="wife" property-ref="husband"/>

     </class>

 </hibernate-mapping>

Wife.hbm.xml 配置文件

 <?xml version="1.0"?>

 <!DOCTYPE hibernate-mapping PUBLIC

         "-//Hibernate/Hibernate Mapping DTD 3.0//EN"

         "http://www.hibernate.org/dtd/hibernate-mapping-3.0.dtd">

 <hibernate-mapping package="com.shore.model">

     <class name="Wife" table="wife_xml">

         <id name="id">

             <generator class="native"/>

         </id>

         <property name="name" type="java.lang.String"/>

         <property name="sex" type="yes_no" />

         <!-- many-to-one:多对一，但加了个unique="true"，就变成了一对一 -->

         <many-to-one name="husband" column="husband_id" unique="true"/>

     </class>

 </hibernate-mapping>

2.3、创建hibernate.cfg.xml 核心配置文件

 <?xml version='1.0' encoding='utf-8'?>

 <!DOCTYPE hibernate-configuration PUBLIC

         "-//Hibernate/Hibernate Configuration DTD 3.0//EN"

         "http://www.hibernate.org/dtd/hibernate-configuration-3.0.dtd">

 <hibernate-configuration>

     <session-factory>

         <!-- Database connection settings -->

         <property name="connection.driver_class">com.mysql.jdbc.Driver</property>

         <property name="connection.url">jdbc:mysql://localhost:3306/hibernate</property>

         <property name="connection.username">root</property>

         <property name="connection.password">123456</property>

         <property name="dialect">org.hibernate.dialect.MySQLDialect</property>

         <property name="cache.provider_class">org.hibernate.cache.NoCacheProvider</property>

         <property name="show_sql">true</property>

         <property name="hbm2ddl.auto">create</property>

         <!-- <mapping class="com.shore.model.Husband" />

         <mapping class="com.shore.model.Wife" /> -->

         <mapping resource="com/shore/model/Husband.hbm.xml" />

         <mapping resource="com/shore/model/Wife.hbm.xml" />

     </session-factory>

 </hibernate-configuration>

2.4、开始测试

 package com.shore.test;

 import org.hibernate.Session;

 import org.hibernate.SessionFactory;

 import org.hibernate.Transaction;

 import org.hibernate.cfg.Configuration;

 import org.junit.AfterClass;

 import org.junit.BeforeClass;

 import org.junit.Test;

 import com.shore.model.Husband;

 import com.shore.model.Wife;

 /**

  * @author DSHORE/2019-9-19

  *

  */

 public class XMLTest {

     public static SessionFactory sessionFactory = null;

     public static Session session = null;

     @BeforeClass

     public static void buildSessionFactory() {

                 //用注解版的话，Configuration()方法，得改用AnnotationConfiguration()方法

         sessionFactory = new Configuration().configure().buildSessionFactory();

     }

     @AfterClass

     public static void close() {

         session.close();

         sessionFactory.close();

     }

     @Test

     public void test(){//数据库表创建完后，插入数据

         session = sessionFactory.openSession();

         Transaction transaction = session.beginTransaction();

         Husband husband = new Husband();

         husband.setName("黄晓明");

         husband.setSex(true);//男

         session.save(husband);

         Wife wife = new Wife();

         wife.setName("AnglaBaby");

         wife.setSex(false);//女

         wife.setHusband(husband);

         session.save(wife);

         transaction.commit();//事务提交

     }

 }

测试结果图：

Hibernate一对一单向关联映射（Annotation+XML实现）：https://www.cnblogs.com/dshore123/p/11545058.html
Hibernate一对一双向关联映射（Annotation+XML实现）：https://www.cnblogs.com/dshore123/p/11545077.html

Hibernate多对一单向关联映射（Annotation+XML实现）：https://www.cnblogs.com/dshore123/p/11553213.html
Hibernate一对多单向关联映射（Annotation+XML实现）：https://www.cnblogs.com/dshore123/p/11553215.html
Hibernate一对多和多对一双向关联映射（Annotation+XML实现）：https://www.cnblogs.com/dshore123/p/11560433.html

Hibernate多对多单向关联映射（Annotation+XML实现）：https://www.cnblogs.com/dshore123/p/11568536.html
Hibernate多对多双向关联映射（Annotation+XML实现）：https://www.cnblogs.com/dshore123/p/11568963.html

原创作者：DSHORE

作者主页：http://www.cnblogs.com/dshore123/

原文出自：https://www.cnblogs.com/dshore123/p/11545077.html

码农公寓

1、Annotation 注解版

2、XML实现 版

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2、XML实现版