Hibernate映射继承

1. Hibernate映射继承

新建项目Hibernate07

hibernate.cfg.xml

<?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>
        <!--数据库连接设置 -->
        <property name="connection.driver_class">com.mysql.jdbc.Driver</property>
        <property name="connection.url">jdbc:mysql://localhost:3306/hibernate4</property>
        <property name="connection.username">root</property>
        <property name="connection.password">root</property>
        <!-- 方言 -->
        <property name="dialect">org.hibernate.dialect.MySQL5Dialect</property>
        <!-- 控制台显示SQL -->
        <property name="show_sql">true</property>
        <!-- 自动更新表结构 -->
        <property name="hbm2ddl.auto">update</property>
        <!-- Mapper -->
        <mapping resource="com/andrew/model/Student.hbm.xml"/>
        <mapping resource="com/andrew/model/LifeImage.hbm.xml"/>
        <mapping resource="com/andrew/model/WorkImage.hbm.xml"/>
        <mapping resource="com/andrew/model/Student2.hbm.xml"/>
        <mapping resource="com/andrew/model/Image2.hbm.xml"/>
        <mapping resource="com/andrew/model/Student3.hbm.xml"/>
        <mapping resource="com/andrew/model/Image3.hbm.xml"/>
    </session-factory>
</hibernate-configuration>

HibernateUtil.java

package com.andrew.util;
import org.hibernate.SessionFactory;
import org.hibernate.boot.registry.StandardServiceRegistryBuilder;
import org.hibernate.cfg.Configuration;
import org.hibernate.service.ServiceRegistry;
public class HibernateUtil {
    private static final SessionFactory sessionFactory = buildSessionFactory();
    private static SessionFactory buildSessionFactory() {
        // 1. 实例化配置文件
        Configuration configuration = new Configuration().configure();
        // 2. 实例化服务登记
        ServiceRegistry serviceRegistry = new StandardServiceRegistryBuilder()
                .applySettings(configuration.getProperties()).build();
        // 3. 获取Session工厂
        return configuration.buildSessionFactory(serviceRegistry);
    }
    public static SessionFactory getSessionFactory() {
        return sessionFactory;
    }
}

1.1) 每个具体类对应一个表

Image.java

package com.andrew.model;
public abstract class Image {
    private int id;
    private String imageName;
    private Student student;
    public int getId() {
        return id;
    }
    public void setId(int id) {
        this.id = id;
    }
    public String getImageName() {
        return imageName;
    }
    public void setImageName(String imageName) {
        this.imageName = imageName;
    }
    public Student getStudent() {
        return student;
    }
    public void setStudent(Student student) {
        this.student = student;
    }
}

LifeImage.java

package com.andrew.model;
public class LifeImage extends Image{
}

LifeImage.hbm.xml

<?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.andrew.model">
    <class name="LifeImage" table="t_lifeImage">
        <id name="id" column="lifeImageId">
            <generator class="native"></generator>
        </id>
        <property name="imageName" column="imageName"></property>
        <many-to-one name="student" column="stuId" class="com.andrew.model.Student"></many-to-one>
    </class>
</hibernate-mapping>

WorkImage.java

package com.andrew.model;
public class WorkImage extends Image{
}

WorkImage.hbm.xml

<?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.andrew.model">
    <class name="WorkImage" table="t_workImage">
        <id name="id" column="workImageId">
            <generator class="native"></generator>
        </id>
        <property name="imageName" column="imageName"></property>
        <many-to-one name="student" column="stuId" class="com.andrew.model.Student"></many-to-one>
    </class>
</hibernate-mapping>

Student.java

package com.andrew.model;
import java.util.Set;
public class Student {
    private int id;
    private String name;
    private Set<Image> images;
    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 Set<Image> getImages() {
        return images;
    }
    public void setImages(Set<Image> images) {
        this.images = images;
    }
}

insert into t_student values(1, '张三');
insert into t_lifeimage values(1, 'image1.jpg', 1);
insert into t_workimage values(1, 'image2.jpg', 1);

StudentTest.java

package com.andrew.service;
import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;
import java.util.Set;
import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.junit.After;
import org.junit.Before;
import org.junit.Test;
import com.andrew.model.Image;
import com.andrew.model.Image2;
import com.andrew.model.Image3;
import com.andrew.model.Student2;
import com.andrew.model.Student3;
import com.andrew.util.HibernateUtil;
public class StudentTest {
    private SessionFactory sessionFactory=HibernateUtil.getSessionFactory();
    private Session session;
    @Before
    public void setUp() throws Exception {
        session=sessionFactory.openSession(); // 1. 生成一个session
        session.beginTransaction(); // 2. 开启事务
    }
    @After
    public void tearDown() throws Exception {
         session.getTransaction().commit(); // 3. 提交事务
         session.close(); // 4. 关闭session
    }
    @Test
    public void testGetAllImages() {
        List<Image> imageList = new ArrayList<Image>();
        int stuId = 1;
        List<Image> lifeImageList = (List<Image>)session.createQuery("from LifeImage l where l.student.id=" + stuId).list();
        imageList.addAll(lifeImageList);
        List<Image> workImageList = (List<Image>)session.createQuery("from WorkImage w where w.student.id=" + stuId).list();
        imageList.addAll(workImageList);
        Iterator it = imageList.iterator();
        while (it.hasNext()) {
            Image image = (Image)it.next();
            System.out.println(image.getImageName());
        }
    }
}

运行结果：
Hibernate: select lifeimage0_.lifeImageId as lifeImag1_2_, lifeimage0_.imageName as imageNam2_2_, lifeimage0_.stuId as stuId3_2_ from t_lifeImage lifeimage0_ where lifeimage0_.stuId=1
Hibernate: select workimage0_.workImageId as workImag1_7_, workimage0_.imageName as imageNam2_7_, workimage0_.stuId as stuId3_7_ from t_workImage workimage0_ where workimage0_.stuId=1
image1.jpg
image2.jpg

1.2) 根类对应一个表

Image2.java

package com.andrew.model;
public class Image2 {
    private int id;
    private String imageName;
    private String imageType;
    private Student2 student;
    public int getId() {
        return id;
    }
    public void setId(int id) {
        this.id = id;
    }
    public String getImageName() {
        return imageName;
    }
    public void setImageName(String imageName) {
        this.imageName = imageName;
    }
    public Student2 getStudent() {
        return student;
    }
    public void setStudent(Student2 student) {
        this.student = student;
    }
    public String getImageType() {
        return imageType;
    }
    public void setImageType(String imageType) {
        this.imageType = imageType;
    }
}

Image2.hbm.xml

<?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.andrew.model">
    <class name="Image2" table="t_image2">
        <id name="id" column="imageId">
            <generator class="native"></generator>
        </id>
        <discriminator column="imageType" type="string"></discriminator>
        <property name="imageName" column="imageName"></property>
        <many-to-one name="student" column="stuId" class="com.andrew.model.Student2"></many-to-one>
        <subclass name="com.andrew.model.LifeImage2" discriminator-value="li"></subclass>
        <subclass name="com.andrew.model.WorkImage2" discriminator-value="wi"></subclass>
    </class>
</hibernate-mapping>

LifeImage2.java

package com.andrew.model;
public class LifeImage2 extends Image2 {
}

WorkImage2.java

package com.andrew.model;
public class WorkImage2 extends Image2{
}

Student2.java

package com.andrew.model;
import java.util.Set;
public class Student2 {
    private int id;
    private String name;
    private Set<Image2> images;
    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 Set<Image2> getImages() {
        return images;
    }
    public void setImages(Set<Image2> images) {
        this.images = images;
    }
}

Student2.hbm.xml

<?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.andrew.model">
    <class name="Student2" table="t_student2">
        <id name="id" column="stuId">
            <generator class="native"></generator>
        </id>
        <property name="name" column="stuName"></property>
        <set name="images">
            <key column="stuId"></key>
            <one-to-many class="com.andrew.model.Image2"/>
        </set>
    </class>
</hibernate-mapping>

insert into t_student2 values(1, '张三');
insert into t_image2 values(1, 'li', 'image1.jpg', 1);
insert into t_image2 values(2, 'wi', 'image2.jpg', 1);

StudentTest.java

package com.andrew.service;
import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;
import java.util.Set;
import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.junit.After;
import org.junit.Before;
import org.junit.Test;
import com.andrew.model.Image;
import com.andrew.model.Image2;
import com.andrew.model.Image3;
import com.andrew.model.Student2;
import com.andrew.model.Student3;
import com.andrew.util.HibernateUtil;
public class StudentTest {
    private SessionFactory sessionFactory=HibernateUtil.getSessionFactory();
    private Session session;
    @Before
    public void setUp() throws Exception {
        session=sessionFactory.openSession(); // 1. 生成一个session
        session.beginTransaction(); // 2. 开启事务
    }
    @After
    public void tearDown() throws Exception {
         session.getTransaction().commit(); // 3. 提交事务
         session.close(); // 4. 关闭session
    }
    @Test
    public void testGetAllImages2() {
        Student2 student2 = (Student2)session.get(Student2.class, 1);
        Set<Image2> images = student2.getImages();
        Iterator it = images.iterator();
        while (it.hasNext()) {
            Image2 image = (Image2)it.next();
            System.out.println(image.getImageName());
        }
    }
}

运行结果：
Hibernate: select student2x0_.stuId as stuId1_5_0_, student2x0_.stuName as stuName2_5_0_ from t_student2 student2x0_ where student2x0_.stuId=?
Hibernate: select images0_.stuId as stuId4_5_0_, images0_.imageId as imageId1_0_0_, images0_.imageId as imageId1_0_1_, images0_.imageName as imageNam3_0_1_, images0_.stuId as stuId4_0_1_, images0_.imageType as imageTyp2_0_1_ from t_image2 images0_ where images0_.stuId=?
image2.jpg
image1.jpg

1.3) 每个类对应一个表

Image3.java

package com.andrew.model;
public class Image3 {
    private int id;
    private String imageName;
    private Student3 student;
    public int getId() {
        return id;
    }
    public void setId(int id) {
        this.id = id;
    }
    public String getImageName() {
        return imageName;
    }
    public void setImageName(String imageName) {
        this.imageName = imageName;
    }
    public Student3 getStudent() {
        return student;
    }
    public void setStudent(Student3 student) {
        this.student = student;
    }
}

Image3.hbm.xml

<?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.andrew.model">
    <class name="Image3" table="t_image3">
        <id name="id" column="imageId">
            <generator class="native"></generator>
        </id>
        <property name="imageName" column="imageName"></property>
        <many-to-one name="student" column="stuId" class="com.andrew.model.Student3"></many-to-one>
        <joined-subclass name="com.andrew.model.LifeImage3" table="t_lifeImage3">
            <key column="lifeImageId"></key>
        </joined-subclass>
        <joined-subclass name="com.andrew.model.WorkImage3" table="t_workImage3">
            <key column="workImageId"></key>
        </joined-subclass>
    </class>
</hibernate-mapping>

LifeImage2.java

package com.andrew.model;
public class LifeImage3 extends Image3{
}

WorkImage3.java

package com.andrew.model;
public class WorkImage3 extends Image3{
}

Student3.java

package com.andrew.model;
import java.util.Set;
public class Student3 {
    private int id;
    private String name;
    private Set<Image3> images;
    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 Set<Image3> getImages() {
        return images;
    }
    public void setImages(Set<Image3> images) {
        this.images = images;
    }
}

Student3.hbm.xml

<?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.andrew.model">
    <class name="Student3" table="t_student3">
        <id name="id" column="stuId">
            <generator class="native"></generator>
        </id>
        <property name="name" column="stuName"></property>
        <set name="images">
            <key column="stuId"></key>
            <one-to-many class="com.andrew.model.Image3"/>
        </set>
    </class>
</hibernate-mapping>

insert into t_student3 values(1, '张三');
insert into t_image3 values(1, 'image11.jpg', 1);
insert into t_image3 values(2, 'image22.jpg', 1);
insert into t_lifeimage3 values(1);
insert into t_workimage3 values(2);

StudentTest.java

package com.andrew.service;
import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;
import java.util.Set;
import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.junit.After;
import org.junit.Before;
import org.junit.Test;
import com.andrew.model.Image;
import com.andrew.model.Image2;
import com.andrew.model.Image3;
import com.andrew.model.Student2;
import com.andrew.model.Student3;
import com.andrew.util.HibernateUtil;
public class StudentTest {
    private SessionFactory sessionFactory=HibernateUtil.getSessionFactory();
    private Session session;
    @Before
    public void setUp() throws Exception {
        session=sessionFactory.openSession(); // 1. 生成一个session
        session.beginTransaction(); // 2. 开启事务
    }
    @After
    public void tearDown() throws Exception {
         session.getTransaction().commit(); // 3. 提交事务
         session.close(); // 4. 关闭session
    }
    @Test
    public void testGetAllImages3() {
        Student3 student3 = (Student3)session.get(Student3.class, 1);
        Set<Image3> images = student3.getImages();
        Iterator it = images.iterator();
        while (it.hasNext()) {
            Image3 image = (Image3)it.next();
            System.out.println(image.getImageName());
        }
    }
}

运行结果：
Hibernate: select student3x0_.stuId as stuId1_6_0_, student3x0_.stuName as stuName2_6_0_ from t_student3 student3x0_ where student3x0_.stuId=?
Hibernate: select images0_.stuId as stuId3_6_0_, images0_.imageId as imageId1_1_0_, images0_.imageId as imageId1_1_1_, images0_.imageName as imageNam2_1_1_, images0_.stuId as stuId3_1_1_, case when images0_1_.lifeImageId is not null then 1 when images0_2_.workImageId is not null then 2 when images0_.imageId is not null then 0 end as clazz_1_ from t_image3 images0_ left outer join t_lifeImage3 images0_1_ on images0_.imageId=images0_1_.lifeImageId left outer join t_workImage3 images0_2_ on images0_.imageId=images0_2_.workImageId where images0_.stuId=?
image22.jpg
image11.jpg