Hibernate--对象关系

在hibernate中，关联关系映射分为单向关联和双向关联。共有七种关系

　　·@Many To One

　　·@One To Many（单向）

　　·@One To Many（多向）

　　·@One To One（单向）

　　·@One To One（多向）

　　·@Many To Many（单向）

　　·@Many To Many（多向）

　　hibernate在维护这几种关系的时候，要不通过连接表，要不通过外键的方式。

@Many To One

　　这是一种最常见的关系，hibernate是通过在many的一方加入one的一个主键作为外键的方式来管理关系的。

　　此时的多的一方和一的一方，需要各自管理，分别保存，也可以在many-to-one的配置中加入级联属性，则在保存多的一端的时候，会自动保存一的一端

先看配置文件版

package com.fuwh.model;
//one
public class Father {private int id;private String 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;}}

package com.fuwh.model;
//Many
public class Child {private int id;private String name;//在many的一端中加入one作为一个属性变量private Father father;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 Father getFather() {return father;}public void setFather(Father father) {this.father = father;}}

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE hibernate-mapping PUBLIC "-//Hibernate/Hibernate Mapping DTD 3.0//EN" "http://www.hibernate.org/dtd/hibernate-mapping-3.0.dtd"><!-- 这是实体类和表的映射关系的配置文件 -->
<hibernate-mapping package="com.fuwh.model"><class name="Father" table="t_father"><id name="id" column="fatherId"><generator class="native"></generator></id><property name="name" column="fatherName"></property></class></hibernate-mapping>

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE hibernate-mapping PUBLIC "-//Hibernate/Hibernate Mapping DTD 3.0//EN" "http://www.hibernate.org/dtd/hibernate-mapping-3.0.dtd">

<!-- 这是实体类和表的映射关系的配置文件 -->
<hibernate-mapping package="com.fuwh.model"><class name="Child" table="t_child"><id name="id" column="childId"><generator class="native"></generator></id><property name="name" column="childName"></property><!-- 单向多(child)对一(father)的关系会在多(child)的一方生成的表中添加一个外键，指向一(father)的主键需要在多(child)的一方配置many-to-onename:指定类中的Father对象变量column：指定外键名字
　　　　　　　cascade:表示级联操作，包含以下集中取值none（默认），all，persist, merge, delete, save-update, evict, replicate,lock and refresh，delete-orphan ;可以用逗号隔开，表示几个取值，all代表所有的-->
        <many-to-one name="father" column="father_Id" cascade="all"></many-to-one></class></hibernate-mapping>

<?xml version='1.0' encoding='utf-8'?>
<!DOCTYPE hibernate-configuration PUBLIC
"-//Hibernate/Hibernate Configuration DTD//EN"
"http://hibernate.sourceforge.net/hibernate-configuration-3.0.dtd"><hibernate-configuration><session-factory><!-- 数据库连接设置 --><property name="hibernate.connection.driver_class">com.mysql.jdbc.Driver</property><property name="hibernate.connection.url">jdbc:mysql://localhost:3306/hibernate</property><property name="hibernate.connection.username">root</property><property name="hibernate.connection.password">mysqladmin</property><!--指定方言，表明用的是哪种数据库，也可以不指定，hibernate默认会翻译成正确的数据库脚本方言可以在 hibernate-release-xx.xx/project/etc/hibernate.properties 中查找--><property name="hibernate.dialect">MySQL5</property><!-- 设定时候更新表结构，不存在或自动创建 --><property name="hibernate.hbm2ddl.auto">update</property><!-- 配置 在后台打印出sql语句 --><property name="hibernate.show_sql">true</property><property name="hibernate.format_sql">true</property><!-- 引入实体类和表的映射文件 --><mapping resource="/com/fuwh/model/Father.hbm.xml"/><mapping resource="/com/fuwh/model/Child.hbm.xml"/></session-factory></hibernate-configuration>

package com.fuwh.service;import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.hibernate.boot.MetadataSources;
import org.hibernate.boot.registry.StandardServiceRegistry;
import org.hibernate.boot.registry.StandardServiceRegistryBuilder;
import org.junit.After;
import org.junit.Before;
import org.junit.Test;public class DoTest {//标准的sessionFactory取得方式private SessionFactory sessionFactory;@Beforepublic void setUp() throws Exception {final StandardServiceRegistry registry=new StandardServiceRegistryBuilder().configure().build();try {sessionFactory=new MetadataSources(registry).buildMetadata().buildSessionFactory();} catch (Exception e) {// TODO: handle exception
            StandardServiceRegistryBuilder.destroy(registry);}}@Afterpublic void tearDown() throws Exception {if(sessionFactory != null){sessionFactory.close();}}@Testpublic void testAdd() {Session session=sessionFactory.openSession();session.beginTransaction();session.getTransaction().commit();session.close();}}

执行空的测试语句，生成的sql文如下

Hibernate: create table t_child (childId integer not null auto_increment,childName varchar(255),father_Id integer,primary key (childId))
Hibernate: create table t_father (fatherId integer not null auto_increment,fatherName varchar(255),primary key (fatherId))
Hibernate: alter table t_child add constraint FKg4qwua9ltkkkfik7fsvubyou7 foreign key (father_Id) references t_father (fatherId)

操作表中的数据

package com.fuwh.service;import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.hibernate.boot.MetadataSources;
import org.hibernate.boot.registry.StandardServiceRegistry;
import org.hibernate.boot.registry.StandardServiceRegistryBuilder;
import org.junit.After;
import org.junit.Before;
import org.junit.Test;import com.fuwh.model.Child;
import com.fuwh.model.Father;public class DoTest {//标准的sessionFactory取得方式private SessionFactory sessionFactory;@Beforepublic void setUp() throws Exception {final StandardServiceRegistry registry=new StandardServiceRegistryBuilder().configure().build();try {sessionFactory=new MetadataSources(registry).buildMetadata().buildSessionFactory();} catch (Exception e) {// TODO: handle exception
            e.printStackTrace();StandardServiceRegistryBuilder.destroy(registry);}}@Afterpublic void tearDown() throws Exception {if(sessionFactory != null){sessionFactory.close();}}@Testpublic void testAdd() {Session session=sessionFactory.openSession();session.beginTransaction();Father father=new Father();father.setName("爸爸");//因为在多的一断配置了级联属性为all，就表明把操作都交给了多的一端来维护关系，不需要保存father对象//在保存child的时候，会自动保存father
        Child child1=new Child();child1.setName("儿子1");child1.setFather(father);Child child2=new Child();child2.setName("儿子2");child2.setFather(father);session.save(child1);session.save(child2);

session.getTransaction().commit();session.close();}
}

生成的sql文

Hibernate: insert intot_father(fatherName) values(?)
Hibernate: insert intot_child(childName, father_Id) values(?, ?)
Hibernate: insert intot_child(childName, father_Id) values(?, ?)

注解版

package com.fuwh.mto;import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.Id;import org.hibernate.annotations.GenericGenerator;@Entity
public class Father {@Id@GeneratedValue(generator="_native")@GenericGenerator(name="_native",strategy="native")private int id;@Column(name="fatherName")private String 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;}}

package com.fuwh.mto;import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.ForeignKey;
import javax.persistence.GeneratedValue;
import javax.persistence.Id;
import javax.persistence.JoinColumn;
import javax.persistence.ManyToOne;import org.hibernate.annotations.GenericGenerator;@Entity
public class Child {@Id@GeneratedValue(generator="_native")@GenericGenerator(name="_native",strategy="native")private int id;@Column(name="childName")private String name;/*** 定义多对一* JoinCloumn中的name指定外键的列名，foreignkey中指定定义的外键的名字* 这一列也可以不加，不加就是默认的设置*/@ManyToOne(cascade=CascadeType.ALL)@JoinColumn(name="father_id",foreignKey=@ForeignKey(name="FATHER_ID_FK"))private Father father;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 Father getFather() {return father;}public void setFather(Father father) {this.father = father;}}

package com.fuwh.service;import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.hibernate.boot.MetadataSources;
import org.hibernate.boot.registry.StandardServiceRegistry;
import org.hibernate.boot.registry.StandardServiceRegistryBuilder;
import org.junit.After;
import org.junit.Before;
import org.junit.Test;import com.fuwh.mto.Child;
import com.fuwh.mto.Father;public class DoTest {//标准的sessionFactory取得方式private SessionFactory sessionFactory;@Beforepublic void setUp() throws Exception {final StandardServiceRegistry registry=new StandardServiceRegistryBuilder().configure().build();try {sessionFactory=new MetadataSources(registry).buildMetadata().buildSessionFactory();} catch (Exception e) {// TODO: handle exception
            e.printStackTrace();StandardServiceRegistryBuilder.destroy(registry);}}@Afterpublic void tearDown() throws Exception {if(sessionFactory != null){sessionFactory.close();}}@Testpublic void testAdd() {Session session=sessionFactory.openSession();session.beginTransaction();Father father=new Father();father.setName("爸爸");Child child1=new Child();child1.setName("儿子一");child1.setFather(father);Child child2=new Child();child2.setName("儿子二");child2.setFather(father);session.save(child1);session.save(child2);session.getTransaction().commit();session.close();}
}

@One To Many单向

　　@One To Many关系把一个父节点和多个子节点联系起来，如果在子节点没有一个@Many To One和@One To Many相匹配的话，那就是一个单向的@One To Many，否则的话就是一个多向的@One To Many，并且可以在任意一边来维护关系。

package com.fuwh.model;import java.util.ArrayList;
import java.util.List;public class Father {private int id;private String name;private List<Child> children=new ArrayList<Child>();public List<Child> getChildren() {return children;}public void setChildren(List<Child> children) {this.children = children;}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;}}

package com.fuwh.model;public class Child {private int id;private String 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;}}

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE hibernate-mapping PUBLIC "-//Hibernate/Hibernate Mapping DTD 3.0//EN" "http://www.hibernate.org/dtd/hibernate-mapping-3.0.dtd"><!-- 这是实体类和表的映射关系的配置文件 -->
<hibernate-mapping package="com.fuwh.model"><class name="Child" table="t_child"><id name="id" column="childId"><generator class="native"></generator></id><property name="name" column="childName"></property></class></hibernate-mapping>

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE hibernate-mapping PUBLIC "-//Hibernate/Hibernate Mapping DTD 3.0//EN" "http://www.hibernate.org/dtd/hibernate-mapping-3.0.dtd"><!-- 这是实体类和表的映射关系的配置文件 -->
<hibernate-mapping package="com.fuwh.model"><class name="Father" table="t_father"><id name="id" column="fatherId"><generator class="native"></generator></id><property name="name" column="fatherName"></property><set name="children" cascade="true"><key column="father_Id"></key><one-to-many class="com.fuwh.model.Child"/></set></class></hibernate-mapping>

package com.fuwh.service;import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.hibernate.boot.MetadataSources;
import org.hibernate.boot.registry.StandardServiceRegistry;
import org.hibernate.boot.registry.StandardServiceRegistryBuilder;
import org.junit.After;
import org.junit.Before;
import org.junit.Test;public class DoTest {//标准的sessionFactory取得方式private SessionFactory sessionFactory;@Beforepublic void setUp() throws Exception {final StandardServiceRegistry registry=new StandardServiceRegistryBuilder().configure().build();try {sessionFactory=new MetadataSources(registry).buildMetadata().buildSessionFactory();} catch (Exception e) {// TODO: handle exception
            e.printStackTrace();StandardServiceRegistryBuilder.destroy(registry);}}@Afterpublic void tearDown() throws Exception {if(sessionFactory != null){sessionFactory.close();}}@Testpublic void testAdd() {Session session=sessionFactory.openSession();session.beginTransaction();session.getTransaction().commit();session.close();}
}

生成的sql文

Hibernate: create table t_child (childId integer not null auto_increment,childName varchar(255),
　　　　 father_Id integer,
        primary key (childId))
Hibernate: create table t_father (fatherId integer not null auto_increment,fatherName varchar(255),primary key (fatherId))
Hibernate: alter table t_child add constraint FKev9uk6ojrjsv10ba9qoa4yhsy foreign key (father_Id) references t_father (fatherId)

注解版

package com.fuwh.otm;import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.Id;import org.hibernate.annotations.GenericGenerator;@Entity
public class Child {@Id@GeneratedValue(generator="_native")@GenericGenerator(name="_native",strategy="native")private int id;@Column(name="childName")private String 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;}}

package com.fuwh.otm;import java.util.ArrayList;
import java.util.List;import javax.persistence.CascadeType;
import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.Id;
import javax.persistence.OneToMany;import org.hibernate.annotations.GenericGenerator;@Entity
public class Father {@Id@GeneratedValue(generator="_native")@GenericGenerator(name="_native",strategy="native")private int id;@Column(name="fatherName")private String name;//orphanRemoval:表示在删除集合中的child的时候，也会删除child表中的相应纪录@OneToMany(cascade=CascadeType.ALL,orphanRemoval=true)private List<Child> children=new ArrayList<Child>(); public List<Child> getChildren() {return children;}public void setChildren(List<Child> children) {this.children = children;}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;}}

package com.fuwh.service;import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.hibernate.boot.MetadataSources;
import org.hibernate.boot.registry.StandardServiceRegistry;
import org.hibernate.boot.registry.StandardServiceRegistryBuilder;
import org.junit.After;
import org.junit.Before;
import org.junit.Test;import com.fuwh.otm.Child;
import com.fuwh.otm.Father;public class DoTest {//标准的sessionFactory取得方式private SessionFactory sessionFactory;@Beforepublic void setUp() throws Exception {final StandardServiceRegistry registry=new StandardServiceRegistryBuilder().configure().build();try {sessionFactory=new MetadataSources(registry).buildMetadata().buildSessionFactory();} catch (Exception e) {// TODO: handle exception
            e.printStackTrace();StandardServiceRegistryBuilder.destroy(registry);}}@Afterpublic void tearDown() throws Exception {if(sessionFactory != null){sessionFactory.close();}}@Testpublic void testAdd() {Session session=sessionFactory.openSession();session.beginTransaction();Father father1=new Father();father1.setName("爸爸1");Father father2=new Father();father2.setName("爸爸2");Child child1=new Child();child1.setName("儿子一");Child child2=new Child();child2.setName("儿子二");father1.getChildren().add(child1);father1.getChildren().add(child2);session.save(father1);session.getTransaction().commit();session.close();}
}

@One To Many双向

package com.fuwh.model;public class Child {private int id;private String name;private Father father;public Father getFather() {return father;}public void setFather(Father father) {this.father = father;}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;}}

package com.fuwh.model;import java.util.HashSet;
import java.util.Set;public class Father {private int id;private String name;private Set<Child> children=new HashSet<Child>();public Set<Child> getChildren() {return children;}public void setChildren(Set<Child> children) {this.children = children;}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;}}

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE hibernate-mapping PUBLIC "-//Hibernate/Hibernate Mapping DTD 3.0//EN" "http://www.hibernate.org/dtd/hibernate-mapping-3.0.dtd"><!-- 这是实体类和表的映射关系的配置文件 -->
<hibernate-mapping package="com.fuwh.model"><class name="Father" table="t_father"><id name="id" column="fatherId"><generator class="native"></generator></id><property name="name" column="fatherName"></property><set name="children"><key column="father_Id"/><one-to-many class="com.fuwh.model.Child"/></set></class></hibernate-mapping>

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE hibernate-mapping PUBLIC "-//Hibernate/Hibernate Mapping DTD 3.0//EN" "http://www.hibernate.org/dtd/hibernate-mapping-3.0.dtd"><!-- 这是实体类和表的映射关系的配置文件 -->
<hibernate-mapping package="com.fuwh.model"><class name="Child" table="t_child"><id name="id" column="childId"><generator class="native"></generator></id><property name="name" column="childName"></property><many-to-one name="father" column="father_Id" cascade="all"></many-to-one></class></hibernate-mapping>

package com.fuwh.service;import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.hibernate.boot.MetadataSources;
import org.hibernate.boot.registry.StandardServiceRegistry;
import org.hibernate.boot.registry.StandardServiceRegistryBuilder;
import org.junit.After;
import org.junit.Before;
import org.junit.Test;import com.fuwh.model.Child;
import com.fuwh.model.Father;public class DoTest {//标准的sessionFactory取得方式private SessionFactory sessionFactory;@Beforepublic void setUp() throws Exception {final StandardServiceRegistry registry=new StandardServiceRegistryBuilder().configure().build();try {sessionFactory=new MetadataSources(registry).buildMetadata().buildSessionFactory();} catch (Exception e) {// TODO: handle exception
            e.printStackTrace();StandardServiceRegistryBuilder.destroy(registry);}}@Afterpublic void tearDown() throws Exception {if(sessionFactory != null){sessionFactory.close();}}@Testpublic void testAdd() {Session session=sessionFactory.openSession();session.beginTransaction();Father father=new Father();father.setName("爸爸");Child child1=new Child();child1.setName("儿子1");Child child2=new Child();child2.setName("儿子2");child1.setFather(father);child2.setFather(father);father.getChildren().add(child1);father.getChildren().add(child2);session.save(child1);session.save(child2);session.getTransaction().commit();session.close();}
}

生成的sql

Hibernate: selectfather0_.fatherId as fatherId1_1_0_,father0_.fatherName as fatherNa2_1_0_ fromt_father father0_ wherefather0_.fatherId=?
Hibernate: selectchild0_.childId as childId1_0_0_,child0_.childName as childNam2_0_0_,child0_.father_Id as father_I3_0_0_ fromt_child child0_ wherechild0_.childId=?
Hibernate: selectchildren0_.father_Id as father_I3_0_0_,children0_.childId as childId1_0_0_,children0_.childId as childId1_0_1_,children0_.childName as childNam2_0_1_,children0_.father_Id as father_I3_0_1_ fromt_child children0_ wherechildren0_.father_Id=?
Hibernate: updatet_child setchildName=?,father_Id=? wherechildId=?
Hibernate: updatet_child setfather_Id=? wherechildId=?

注解版

package com.fuwh.otmbi;import java.util.ArrayList;
import java.util.List;import javax.persistence.CascadeType;
import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.Id;
import javax.persistence.OneToMany;import org.hibernate.annotations.GenericGenerator;@Entity
public class Father {@Id@GeneratedValue(generator="_native")@GenericGenerator(name="_native",strategy="native")private int id;@Column(name="fatherName")private String name;/*** orphanRemoval:表示在删除集合中的child的时候，也会删除child表中的相应纪录* mappedBy/inverse:表示由另一方来维护关系* */@OneToMany(mappedBy="father",cascade=CascadeType.ALL,orphanRemoval=true)private List<Child> children=new ArrayList<Child>(); public List<Child> getChildren() {return children;}public void setChildren(List<Child> children) {this.children = children;}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;}}

package com.fuwh.otmbi;import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.Id;
import javax.persistence.ManyToOne;import org.hibernate.annotations.GenericGenerator;@Entity
public class Child {@Id@GeneratedValue(generator="_native")@GenericGenerator(name="_native",strategy="native")private int id;@Column(name="childName")private String name;@ManyToOneprivate Father father;public Father getFather() {return father;}public void setFather(Father father) {this.father = father;}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;}}

package com.fuwh.service;import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.hibernate.boot.MetadataSources;
import org.hibernate.boot.registry.StandardServiceRegistry;
import org.hibernate.boot.registry.StandardServiceRegistryBuilder;
import org.junit.After;
import org.junit.Before;
import org.junit.Test;import com.fuwh.otmbi.Child;
import com.fuwh.otmbi.Father;public class DoTest {//标准的sessionFactory取得方式private SessionFactory sessionFactory;@Beforepublic void setUp() throws Exception {final StandardServiceRegistry registry=new StandardServiceRegistryBuilder().configure().build();try {sessionFactory=new MetadataSources(registry).buildMetadata().buildSessionFactory();} catch (Exception e) {// TODO: handle exception
            e.printStackTrace();StandardServiceRegistryBuilder.destroy(registry);}}@Afterpublic void tearDown() throws Exception {if(sessionFactory != null){sessionFactory.close();}}@Testpublic void testAdd() {Session session=sessionFactory.openSession();session.beginTransaction();Father father1=new Father();father1.setName("爸爸1");Child child1=new Child();child1.setName("儿子一");child1.setFather(father1);Child child2=new Child();child2.setName("儿子二");child2.setFather(father1);father1.getChildren().add(child1);father1.getChildren().add(child2);session.save(father1);session.getTransaction().commit();session.close();}
}

@One To One单向

　　单向的关系又可以分为基于主键的关联和基于外键的关联。

基于外键

package com.fuwh.model;public class Wife {private int id;private String 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;}}

package com.fuwh.model;public class Husband {private int id;private String name;private Wife wife;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 Wife getWife() {return wife;}public void setWife(Wife wife) {this.wife = wife;}}

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE hibernate-mapping PUBLIC "-//Hibernate/Hibernate Mapping DTD 3.0//EN" "http://www.hibernate.org/dtd/hibernate-mapping-3.0.dtd"><!-- 这是实体类和表的映射关系的配置文件 -->
<hibernate-mapping package="com.fuwh.model"><class name="Wife" table="t_wife"><id name="id" column="wifeId"><generator class="native"></generator></id><property name="name" column="wifeName"></property></class></hibernate-mapping>

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE hibernate-mapping PUBLIC "-//Hibernate/Hibernate Mapping DTD 3.0//EN" "http://www.hibernate.org/dtd/hibernate-mapping-3.0.dtd"><!-- 这是实体类和表的映射关系的配置文件 -->
<hibernate-mapping package="com.fuwh.model"><class name="Husband" table="t_husband"><id name="id" column="husbandId"><!-- 主键生成策略为 外键 指向 wife--><generator class="foreign"><param name="property">wife</param></generator></id><property name="name" column="husbandName"></property><one-to-one name="wife" constrained="true"/></class></hibernate-mapping>

package com.fuwh.service;import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.hibernate.boot.MetadataSources;
import org.hibernate.boot.registry.StandardServiceRegistry;
import org.hibernate.boot.registry.StandardServiceRegistryBuilder;
import org.junit.After;
import org.junit.Before;
import org.junit.Test;import com.fuwh.model.Child;
import com.fuwh.model.Father;
import com.fuwh.model.Husband;
import com.fuwh.model.Wife;public class DoTest {//标准的sessionFactory取得方式private SessionFactory sessionFactory;@Beforepublic void setUp() throws Exception {final StandardServiceRegistry registry=new StandardServiceRegistryBuilder().configure().build();try {sessionFactory=new MetadataSources(registry).buildMetadata().buildSessionFactory();} catch (Exception e) {// TODO: handle exception
            e.printStackTrace();StandardServiceRegistryBuilder.destroy(registry);}}@Afterpublic void tearDown() throws Exception {if(sessionFactory != null){sessionFactory.close();}}@Testpublic void testAdd() {Session session=sessionFactory.openSession();session.beginTransaction();Husband husband=new Husband();Wife wife=new Wife();wife.setName("老婆");husband.setName("老公");husband.setWife(wife);session.save(wife);session.save(husband);session.getTransaction().commit();session.close();}
}

生成的sql文

Hibernate: create table t_husband (husbandId integer not null,husbandName varchar(255),primary key (husbandId))
Hibernate: create table t_wife (wifeId integer not null auto_increment,wifeName varchar(255),primary key (wifeId))
Hibernate: alter table t_husband add constraint FK2tae450lphjy8nciwyrxxlfkv foreign key (husbandId) references t_wife (wifeId)
Hibernate: insert intot_wife(wifeName) values(?)
Hibernate: insert intot_husband(husbandName, husbandId) values(?, ?)

在单向一对一中，hibernate默认是让client-side(上例的Husband)通过外键来管理关系的。

注解版

package com.fuwh.oto;import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.Id;import org.hibernate.annotations.GenericGenerator;@Entity
public class Father {@Id@GeneratedValue(generator="_native")@GenericGenerator(name="_native",strategy="native")private int id;@Column(name="fatherName")private String 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;}}

package com.fuwh.oto;import javax.persistence.CascadeType;
import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.Id;
import javax.persistence.JoinColumn;
import javax.persistence.OneToOne;import org.hibernate.annotations.GenericGenerator;@Entity
public class Child {@Id@GeneratedValue(generator="_native")@GenericGenerator(name="_native",strategy="native")private int id;@Column(name="childName")private String name;@OneToOne(cascade=CascadeType.ALL)@JoinColumn(name="father_id")private Father father;public Father getFather() {return father;}public void setFather(Father father) {this.father = father;}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;}}

package com.fuwh.service;import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.hibernate.boot.MetadataSources;
import org.hibernate.boot.registry.StandardServiceRegistry;
import org.hibernate.boot.registry.StandardServiceRegistryBuilder;
import org.junit.After;
import org.junit.Before;
import org.junit.Test;import com.fuwh.oto.Child;
import com.fuwh.oto.Father;public class DoTest {//标准的sessionFactory取得方式private SessionFactory sessionFactory;@Beforepublic void setUp() throws Exception {final StandardServiceRegistry registry=new StandardServiceRegistryBuilder().configure().build();try {sessionFactory=new MetadataSources(registry).buildMetadata().buildSessionFactory();} catch (Exception e) {// TODO: handle exception
            e.printStackTrace();StandardServiceRegistryBuilder.destroy(registry);}}@Afterpublic void tearDown() throws Exception {if(sessionFactory != null){sessionFactory.close();}}@Testpublic void testAdd() {Session session=sessionFactory.openSession();session.beginTransaction();Father father1=new Father();father1.setName("爸爸1");Child child1=new Child();child1.setName("儿子一");child1.setFather(father1);session.save(child1);session.getTransaction().commit();session.close();}
}

@One-To-One(双向)

package com.fuwh.model;public class Wife {private int id;private String name;private Husband husband;public Husband getHusband() {return husband;}public void setHusband(Husband husband) {this.husband = husband;}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;}}

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE hibernate-mapping PUBLIC "-//Hibernate/Hibernate Mapping DTD 3.0//EN" "http://www.hibernate.org/dtd/hibernate-mapping-3.0.dtd"><!-- 这是实体类和表的映射关系的配置文件 -->
<hibernate-mapping package="com.fuwh.model"><class name="Wife" table="t_wife"><id name="id" column="wifeId"><generator class="native"></generator></id><property name="name" column="wifeName"></property><one-to-one name="husband"/></class></hibernate-mapping>

Hibernate: create table t_husband (husbandId integer not null,husbandName varchar(255),primary key (husbandId))
Hibernate: create table t_wife (wifeId integer not null auto_increment,wifeName varchar(255),primary key (wifeId))
Hibernate: alter table t_husband add constraint FK2tae450lphjy8nciwyrxxlfkv foreign key (husbandId) references t_wife (wifeId)
Hibernate: insert intot_wife(wifeName) values(?)
Hibernate: insert intot_husband(husbandName, husbandId) values(?, ?)

注解版

package com.fuwh.otobi;import javax.persistence.CascadeType;
import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.FetchType;
import javax.persistence.GeneratedValue;
import javax.persistence.Id;
import javax.persistence.OneToOne;import org.hibernate.annotations.GenericGenerator;@Entity
public class Father {@Id@GeneratedValue(generator="_native")@GenericGenerator(name="_native",strategy="native")private int id;@Column(name="fatherName")private String name;@OneToOne(mappedBy="father",cascade=CascadeType.ALL,fetch=FetchType.LAZY)private Child child;public Child getChild() {return child;}public void setChild(Child child) {this.child = child;}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;}}

package com.fuwh.otobi;import javax.persistence.CascadeType;
import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.Id;
import javax.persistence.JoinColumn;
import javax.persistence.OneToOne;import org.hibernate.annotations.GenericGenerator;@Entity
public class Child {@Id@GeneratedValue(generator="_native")@GenericGenerator(name="_native",strategy="native")private int id;@Column(name="childName")private String name;@OneToOne(cascade=CascadeType.ALL)@JoinColumn(name="father_id")private Father father;public Father getFather() {return father;}public void setFather(Father father) {this.father = father;}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;}}

package com.fuwh.service;import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.hibernate.boot.MetadataSources;
import org.hibernate.boot.registry.StandardServiceRegistry;
import org.hibernate.boot.registry.StandardServiceRegistryBuilder;
import org.junit.After;
import org.junit.Before;
import org.junit.Test;import com.fuwh.otobi.Child;
import com.fuwh.otobi.Father;public class DoTest {//标准的sessionFactory取得方式private SessionFactory sessionFactory;@Beforepublic void setUp() throws Exception {final StandardServiceRegistry registry=new StandardServiceRegistryBuilder().configure().build();try {sessionFactory=new MetadataSources(registry).buildMetadata().buildSessionFactory();} catch (Exception e) {// TODO: handle exception
            e.printStackTrace();StandardServiceRegistryBuilder.destroy(registry);}}@Afterpublic void tearDown() throws Exception {if(sessionFactory != null){sessionFactory.close();}}@Testpublic void testAdd() {Session session=sessionFactory.openSession();session.beginTransaction();Father father1=new Father();father1.setName("爸爸1");Child child1=new Child();child1.setName("儿子一");child1.setFather(father1);session.save(child1);session.getTransaction().commit();session.close();}
}

@Many-To-Many（单向）

　　@Many-To-Many关系需要一个连接表来连接两张表。

package com.fuwh.model;public class Wife {private int id;private String 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;}}

package com.fuwh.model;import java.util.HashSet;
import java.util.Set;public class Husband {private int id;private String name;private Set<Wife> wives=new HashSet<Wife>();public Set<Wife> getWives() {return wives;}public void setWives(Set<Wife> wives) {this.wives = wives;}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;}}

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE hibernate-mapping PUBLIC "-//Hibernate/Hibernate Mapping DTD 3.0//EN" "http://www.hibernate.org/dtd/hibernate-mapping-3.0.dtd"><!-- 这是实体类和表的映射关系的配置文件 -->
<hibernate-mapping package="com.fuwh.model"><class name="Wife" table="t_wife"><id name="id" column="wifeId"><generator class="native"></generator></id><property name="name" column="wifeName"></property></class></hibernate-mapping>

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE hibernate-mapping PUBLIC "-//Hibernate/Hibernate Mapping DTD 3.0//EN" "http://www.hibernate.org/dtd/hibernate-mapping-3.0.dtd"><!-- 这是实体类和表的映射关系的配置文件 -->
<hibernate-mapping package="com.fuwh.model"><class name="Husband" table="t_husband"><id name="id" column="husbandId"><generator class="native"/></id><property name="name" column="husbandName"></property><set name="wives" cascade="all"><!-- key 指定连接表的主键列 many-to-many：中的列指定连接另一端的列，或对应的类--><key column="husband_id"></key><many-to-many column="wife_id" class="com.fuwh.model.Wife"></many-to-many></set></class></hibernate-mapping>

package com.fuwh.service;import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.hibernate.boot.MetadataSources;
import org.hibernate.boot.registry.StandardServiceRegistry;
import org.hibernate.boot.registry.StandardServiceRegistryBuilder;
import org.junit.After;
import org.junit.Before;
import org.junit.Test;import com.fuwh.model.Child;
import com.fuwh.model.Father;
import com.fuwh.model.Husband;
import com.fuwh.model.Wife;public class DoTest {//标准的sessionFactory取得方式private SessionFactory sessionFactory;@Beforepublic void setUp() throws Exception {final StandardServiceRegistry registry=new StandardServiceRegistryBuilder().configure().build();try {sessionFactory=new MetadataSources(registry).buildMetadata().buildSessionFactory();} catch (Exception e) {// TODO: handle exception
            e.printStackTrace();StandardServiceRegistryBuilder.destroy(registry);}}@Afterpublic void tearDown() throws Exception {if(sessionFactory != null){sessionFactory.close();}}@Testpublic void testAdd() {Session session=sessionFactory.openSession();session.beginTransaction();Husband husband=new Husband();husband.setName("老公");Wife wife1=new Wife();wife1.setName("老婆1");Wife wife2=new Wife();wife2.setName("老婆2");husband.getWives().add(wife1);husband.getWives().add(wife2);
//        session.save(wife);
        session.save(husband);session.getTransaction().commit();session.close();}
}

注解

package com.fuwh.model;import java.util.ArrayList;
import java.util.List;import javax.persistence.CascadeType;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.Id;
import javax.persistence.ManyToMany;import org.hibernate.annotations.GenericGenerator;@Entity(name="person")
public class Person {@Id@GeneratedValue(generator="_native")@GenericGenerator(name="_native",strategy="native")private int id;@ManyToMany(cascade=CascadeType.ALL)private List<Address> addresses=new ArrayList<Address>();public int getId() {return id;}public void setId(int id) {this.id = id;}public List<Address> getAddresses() {return addresses;}public void setAddresses(List<Address> addresses) {this.addresses = addresses;}}

package com.fuwh.model;import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.Id;import org.hibernate.annotations.GenericGenerator;@Entity(name="address")
public class Address {@Id@GeneratedValue(generator="_native")@GenericGenerator(name="_native",strategy="native")private int id;@Column(name="street")private String street;private String number;public int getId() {return id;}public void setId(int id) {this.id = id;}public String getStreet() {return street;}public void setStreet(String street) {this.street = street;}public String getNumber() {return number;}public void setNumber(String number) {this.number = number;}}

package com.fuwh.service;import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.hibernate.boot.MetadataSources;
import org.hibernate.boot.registry.StandardServiceRegistry;
import org.hibernate.boot.registry.StandardServiceRegistryBuilder;
import org.junit.After;
import org.junit.Before;
import org.junit.Test;import com.fuwh.model.Address;
import com.fuwh.model.Person;public class DoTest {//标准的sessionFactory取得方式private SessionFactory sessionFactory;@Beforepublic void setUp() throws Exception {final StandardServiceRegistry registry=new StandardServiceRegistryBuilder().configure().build();try {sessionFactory=new MetadataSources(registry).buildMetadata().buildSessionFactory();} catch (Exception e) {// TODO: handle exception
            e.printStackTrace();StandardServiceRegistryBuilder.destroy(registry);}}@Afterpublic void tearDown() throws Exception {if(sessionFactory != null){sessionFactory.close();}}@Testpublic void testAdd() {Session session=sessionFactory.openSession();session.beginTransaction();Person person=new Person();Address address1=new Address();address1.setNumber("1001");address1.setStreet("java路");Address address2=new Address();address2.setNumber("1002");address2.setStreet("php路");person.getAddresses().add(address1);person.getAddresses().add(address2);session.save(person);session.flush();//删除的时候会把所有的address的id的记录删除，在插入其他不用删除的
        person.getAddresses().remove(address1);session.getTransaction().commit();session.close();}
}

生成的SQL文

Hibernate: create table address (id integer not null auto_increment,number varchar(255),street varchar(255),primary key (id))
Hibernate: create table person (id integer not null auto_increment,primary key (id))
Hibernate: create table person_address (person_id integer not null,addresses_id integer not null)
Hibernate: alter table person_address add constraint FKkvjdfs4jhjpxa6y3melormp0w foreign key (addresses_id) references address (id)
Hibernate: alter table person_address add constraint FKnndfs0btabect8upo03uwgfxt foreign key (person_id) references person (id)
Hibernate: insert intopersonvalues( )
Hibernate: insert intoaddress(number, street) values(?, ?)
Hibernate: insert intoaddress(number, street) values(?, ?)
Hibernate: insert intoperson_address(person_id, addresses_id) values(?, ?)
Hibernate: insert intoperson_address(person_id, addresses_id) values(?, ?)
Hibernate: delete fromperson_address whereperson_id=?
Hibernate: insert intoperson_address(person_id, addresses_id) values(?, ?)

@Many-To-Many（双向）

package com.fuwh.model;import java.util.HashSet;
import java.util.Set;public class Wife {private int id;private String name;private Set<Husband> husbands=new HashSet<Husband>();public Set<Husband> getHusbands() {return husbands;}public void setHusbands(Set<Husband> husbands) {this.husbands = husbands;}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;}}

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE hibernate-mapping PUBLIC "-//Hibernate/Hibernate Mapping DTD 3.0//EN" "http://www.hibernate.org/dtd/hibernate-mapping-3.0.dtd"><!-- 这是实体类和表的映射关系的配置文件 -->
<hibernate-mapping package="com.fuwh.model"><class name="Wife" table="t_wife"><id name="id" column="wifeId"><generator class="native"></generator></id><property name="name" column="wifeName"></property><!-- 这里必须参照Husband.hbm.xml文件中的连接表的配置，否则会默认生成两个连接表也就是两个单向的多对多    --><set name="husbands" inverse="true" table="husband_wife"><key column="wife_id"></key><many-to-many column="husband_id" class="com.fuwh.model.Husband" ></many-to-many></set></class></hibernate-mapping>

package com.fuwh.service;import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.hibernate.boot.MetadataSources;
import org.hibernate.boot.registry.StandardServiceRegistry;
import org.hibernate.boot.registry.StandardServiceRegistryBuilder;
import org.junit.After;
import org.junit.Before;
import org.junit.Test;import com.fuwh.model.Child;
import com.fuwh.model.Father;
import com.fuwh.model.Husband;
import com.fuwh.model.Wife;public class DoTest {//标准的sessionFactory取得方式private SessionFactory sessionFactory;@Beforepublic void setUp() throws Exception {final StandardServiceRegistry registry=new StandardServiceRegistryBuilder().configure().build();try {sessionFactory=new MetadataSources(registry).buildMetadata().buildSessionFactory();} catch (Exception e) {// TODO: handle exception
            e.printStackTrace();StandardServiceRegistryBuilder.destroy(registry);}}@Afterpublic void tearDown() throws Exception {if(sessionFactory != null){sessionFactory.close();}}@Testpublic void testAdd() {Session session=sessionFactory.openSession();session.beginTransaction();Husband husband1=new Husband();husband1.setName("老公1");Husband husband2=new Husband();husband2.setName("老公2");Wife wife1=new Wife();wife1.setName("老婆1");Wife wife2=new Wife();wife2.setName("老婆2");husband1.getWives().add(wife1);husband1.getWives().add(wife2);wife1.getHusbands().add(husband1);wife1.getHusbands().add(husband2);session.save(husband1);session.save(husband2);session.getTransaction().commit();session.close();}
}

生成的SQL文

Hibernate: create table husband_wife (husband_id integer not null,wife_id integer not null,primary key (husband_id, wife_id))
Hibernate: create table t_husband (husbandId integer not null auto_increment,husbandName varchar(255),primary key (husbandId))
Hibernate: create table t_wife (wifeId integer not null auto_increment,wifeName varchar(255),primary key (wifeId))
Hibernate: alter table husband_wife add constraint FK56txr9ocpn1k0eyc7ax1a2smw foreign key (wife_id) references t_wife (wifeId)
Hibernate: alter table husband_wife add constraint FKsiwjiutn6eoha0iv059pd75fc foreign key (husband_id) references t_husband (husbandId)
Hibernate: insert intot_husband(husbandName) values(?)
Hibernate: insert intot_wife(wifeName) values(?)
Hibernate: insert intot_husband(husbandName) values(?)
Hibernate: insert intot_wife(wifeName) values(?)Hibernate: insert intohusband_wife(husband_id, wife_id) values(?, ?)
Hibernate: insert intohusband_wife(husband_id, wife_id) values(?, ?)

注解

package com.fuwh.mtmbi;import java.util.ArrayList;
import java.util.List;import javax.persistence.CascadeType;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.Id;
import javax.persistence.ManyToMany;import org.hibernate.annotations.GenericGenerator;@Entity(name="person")
public class Person {@Id@GeneratedValue(generator="_native")@GenericGenerator(name="_native",strategy="native")private int id;@ManyToMany(cascade=CascadeType.ALL)private List<Address> addresses=new ArrayList<Address>();public int getId() {return id;}public void setId(int id) {this.id = id;}public List<Address> getAddresses() {return addresses;}public void setAddresses(List<Address> addresses) {this.addresses = addresses;}}

package com.fuwh.mtmbi;import java.util.ArrayList;
import java.util.List;import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.Id;
import javax.persistence.ManyToMany;import org.hibernate.annotations.GenericGenerator;@Entity(name="address")
public class Address {@Id@GeneratedValue(generator="_native")@GenericGenerator(name="_native",strategy="native")private int id;@Column(name="street")private String street;private String number;@ManyToMany(mappedBy="address")private List<Person> owners=new ArrayList<Person>();public int getId() {return id;}public void setId(int id) {this.id = id;}public String getStreet() {return street;}public void setStreet(String street) {this.street = street;}public String getNumber() {return number;}public void setNumber(String number) {this.number = number;}}

package com.fuwh.service;import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.hibernate.boot.MetadataSources;
import org.hibernate.boot.registry.StandardServiceRegistry;
import org.hibernate.boot.registry.StandardServiceRegistryBuilder;
import org.junit.After;
import org.junit.Before;
import org.junit.Test;import com.fuwh.mtmbi.Person;
import com.fuwh.mtmbi.Address;public class DoTest {//标准的sessionFactory取得方式private SessionFactory sessionFactory;@Beforepublic void setUp() throws Exception {final StandardServiceRegistry registry=new StandardServiceRegistryBuilder().configure().build();try {sessionFactory=new MetadataSources(registry).buildMetadata().buildSessionFactory();} catch (Exception e) {// TODO: handle exception
            e.printStackTrace();StandardServiceRegistryBuilder.destroy(registry);}}@Afterpublic void tearDown() throws Exception {if(sessionFactory != null){sessionFactory.close();}}@Testpublic void testAdd() {Session session=sessionFactory.openSession();session.beginTransaction();Person person1=new Person();Person person2=new Person();Address address1=new Address();address1.setNumber("101");Address address2=new Address();address2.setNumber("102");person1.getAddresses().add(address1);person1.getAddresses().add(address2);person2.getAddresses().add(address1);session.save(person1);session.save(person2);session.getTransaction().commit();session.close();}
}

生成的SQL文

Hibernate: create table address (id integer not null auto_increment,number varchar(255),street varchar(255),primary key (id))
Hibernate: create table person (id integer not null auto_increment,primary key (id))
Hibernate: create table person_address (owners_id integer not null,addresses_id integer not null)
Hibernate: alter table person_address add constraint FKkvjdfs4jhjpxa6y3melormp0w foreign key (addresses_id) references address (id)
Hibernate: alter table person_address add constraint FKpts56mn8uttsyi3b63b2cihvo foreign key (owners_id) references person (id)
Hibernate: insert intopersonvalues( )
Hibernate: insert intoaddress(number, street) values(?, ?)
Hibernate: insert intoaddress(number, street) values(?, ?)
Hibernate: insert intopersonvalues( )
Hibernate: insert intoperson_address(owners_id, addresses_id) values(?, ?)
Hibernate: insert intoperson_address(owners_id, addresses_id) values(?, ?)
Hibernate: insert intoperson_address(owners_id, addresses_id) values(?, ?)

转载于:https://www.cnblogs.com/zerotomax/p/6361633.html

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