学步园

Java代码

1. CREATE DATABASE `onetoone`   
2. CHARACTER SET 'utf8';   
3.   
4. USE `onetoone`;   
5.   
6. DROP TABLE IF EXISTS `student`;   
7. CREATE TABLE `student` (   
8.   `id` int(11) NOT NULL auto_increment,   
9.   `name` varchar(255) NOT NULL,   
10.   PRIMARY KEY  (`id`)   
11. ) ENGINE=InnoDB DEFAULT CHARSET=utf8;   
12.   
13. DROP TABLE IF EXISTS `computer`;   
14. CREATE TABLE `computer` (   
15.   `id` int(11) NOT NULL auto_increment,   
16.   `name` varchar(255) NOT NULL,   
17.   `student_id` int(11) ,   
18.   foreign key (`student_id`) references student(`id`),   
19.   PRIMARY KEY  (`id`)   
20. ) ENGINE=InnoDB DEFAULT CHARSET=utf8;  

CREATE DATABASE `onetoone`
CHARACTER SET 'utf8';

USE `onetoone`;

DROP TABLE IF EXISTS `student`;
CREATE TABLE `student` (
  `id` int(11) NOT NULL auto_increment,
  `name` varchar(255) NOT NULL,
  PRIMARY KEY  (`id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8;

DROP TABLE IF EXISTS `computer`;
CREATE TABLE `computer` (
  `id` int(11) NOT NULL auto_increment,
  `name` varchar(255) NOT NULL,
  `student_id` int(11) ,
  foreign key (`student_id`) references student(`id`),
  PRIMARY KEY  (`id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8;

Student.java:

Java代码

1. package com.domain;   
2.   
3.   
4. public class Student implements java.io.Serializable {   
5.   
6.     private Integer id;   
7.   
8.     private String name;   
9.   
10.     private Computer computer;   
11.   
12.     public Student() {   
13.     }   
14.   
15.     public Student(String name) {   
16.         this.name = name;   
17.     }   
18.   
19.     public Integer getId() {   
20.         return this.id;   
21.     }   
22.   
23.     public void setId(Integer id) {   
24.         this.id = id;   
25.     }   
26.   
27.     public String getName() {   
28.         return this.name;   
29.     }   
30.   
31.     public void setName(String name) {   
32.         this.name = name;   
33.     }   
34.   
35.     public Computer getComputer() {   
36.         return computer;   
37.     }   
38.   
39.     public void setComputer(Computer computer) {   
40.         this.computer = computer;   
41.     }   
42.   
43.        
44. }  

package com.domain;


public class Student implements java.io.Serializable {

	private Integer id;

	private String name;

	private Computer computer;

	public Student() {
	}

	public Student(String name) {
		this.name = name;
	}

	public Integer getId() {
		return this.id;
	}

	public void setId(Integer id) {
		this.id = id;
	}

	public String getName() {
		return this.name;
	}

	public void setName(String name) {
		this.name = name;
	}

	public Computer getComputer() {
		return computer;
	}

	public void setComputer(Computer computer) {
		this.computer = computer;
	}

	
}

Computer.java:

Java代码

1. package com.domain;   
2.   
3. public class Computer implements java.io.Serializable {   
4.   
5.     private Integer id;   
6.   
7.     private Student student;   
8.   
9.     private String name;   
10.   
11.   
12.     public Computer() {   
13.     }   
14.   
15.   
16.     public Computer(String name) {   
17.         this.name = name;   
18.     }   
19.   
20.   
21.     public Computer(Student student, String name) {   
22.         this.student = student;   
23.         this.name = name;   
24.     }   
25.   
26.     public Integer getId() {   
27.         return this.id;   
28.     }   
29.   
30.     public void setId(Integer id) {   
31.         this.id = id;   
32.     }   
33.   
34.     public Student getStudent() {   
35.         return this.student;   
36.     }   
37.   
38.     public void setStudent(Student student) {   
39.         this.student = student;   
40.     }   
41.   
42.     public String getName() {   
43.         return this.name;   
44.     }   
45.   
46.     public void setName(String name) {   
47.         this.name = name;   
48.     }   
49.   
50. }  

package com.domain;

public class Computer implements java.io.Serializable {

	private Integer id;

	private Student student;

	private String name;


	public Computer() {
	}


	public Computer(String name) {
		this.name = name;
	}


	public Computer(Student student, String name) {
		this.student = student;
		this.name = name;
	}

	public Integer getId() {
		return this.id;
	}

	public void setId(Integer id) {
		this.id = id;
	}

	public Student getStudent() {
		return this.student;
	}

	public void setStudent(Student student) {
		this.student = student;
	}

	public String getName() {
		return this.name;
	}

	public void setName(String name) {
		this.name = name;
	}

}

Student.hbm.xml:

Java代码

1. <?xml version="1.0" encoding="utf-8"?>   
2. <!DOCTYPE hibernate-mapping PUBLIC "-//Hibernate/Hibernate Mapping DTD 3.0//EN"  
3. "http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd">   
4.   
5. <hibernate-mapping>   
6.     <class name="com.domain.Student" table="student" catalog="onetoone">   
7.         <id name="id" type="java.lang.Integer">   
8.             <column name="id" />   
9.             <generator class="native" />   
10.         </id>   
11.         <property name="name" type="java.lang.String">   
12.             <column name="name" not-null="true" />   
13.         </property>   
14.         <!-- class可以不写，因为根据name的值computer(属性)，会通过反射自动找到属于哪个类的 -->   
15.         <one-to-one cascade="delete,save-update" name="computer" class="com.domain.Computer" property-ref="student"></one-to-one>   
16.     </class>   
17. </hibernate-mapping>  

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

<hibernate-mapping>
    <class name="com.domain.Student" table="student" catalog="onetoone">
        <id name="id" type="java.lang.Integer">
            <column name="id" />
            <generator class="native" />
        </id>
        <property name="name" type="java.lang.String">
            <column name="name" not-null="true" />
        </property>
        <!-- class可以不写，因为根据name的值computer(属性)，会通过反射自动找到属于哪个类的 -->
        <one-to-one cascade="delete,save-update" name="computer" class="com.domain.Computer" property-ref="student"></one-to-one>
    </class>
</hibernate-mapping>

Computer.hbm.xml:

Java代码

1. <?xml version="1.0" encoding="utf-8"?>   
2. <!DOCTYPE hibernate-mapping PUBLIC "-//Hibernate/Hibernate Mapping DTD 3.0//EN"  
3. "http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd">   
4.   
5. <hibernate-mapping>   
6.     <class name="com.domain.Computer" table="computer" catalog="onetoone">   
7.         <id name="id" type="java.lang.Integer">   
8.             <column name="id" />   
9.             <generator class="native" />   
10.         </id>   
11.           
12.         <property name="name" type="java.lang.String">   
13.             <column name="name" not-null="true" />   
14.         </property>   
15.            
16.          <!-- many开头的是代表该表持有外键 -->   
17.         <many-to-one  name="student" class="com.domain.Student"  unique="true">   
18.             <column name="student_id" />   
19.         </many-to-one>   
20.     </class>   
21. </hibernate-mapping>  

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

<hibernate-mapping>
    <class name="com.domain.Computer" table="computer" catalog="onetoone">
        <id name="id" type="java.lang.Integer">
            <column name="id" />
            <generator class="native" />
        </id>
       
        <property name="name" type="java.lang.String">
            <column name="name" not-null="true" />
        </property>
        
         <!-- many开头的是代表该表持有外键 -->
        <many-to-one  name="student" class="com.domain.Student"  unique="true">
            <column name="student_id" />
        </many-to-one>
    </class>
</hibernate-mapping>

测试类：

Java代码

1. package com.domain;   
2.   
3. import org.hibernate.Query;   
4. import org.hibernate.Session;   
5.   
6. import com.util.HibernateSessionFactory;   
7.   
8. public class Test {   
9.        
10.     public static void main(String[] args){   
11.         Session session = HibernateSessionFactory.getSession();   
12.            
13.         //save   
14.         Student student = new Student();   
15.         student.setName("student9");   
16.            
17.         Computer computer = new Computer();   
18.         computer.setName("Intel 9");   
19.            
20.         //computer.setStudent(student)和student.setComputer(computer);都必须要   
21.         computer.setStudent(student);   
22.         student.setComputer(computer);   
23.            
24.         session.save(student);   
25.            
26.         /**  
27.          执行的sql:  
28.          Hibernate: insert into onetoone.student (name) values (?)  
29.          Hibernate: insert into onetoone.computer (name, student_id) values (?, ?)  
30.          */  
31.            
32. //         
33.         session.beginTransaction().commit();   
34.            
35.         //query   
36.            
37. //      String hql = "from Student where name=?";   
38. //      Query query = session.createQuery(hql);   
39. //      query.setString(0, "student3");   
40. //         
41. //      Student student = (Student)query.uniqueResult();   
42. //      System.out.println(student.getId() + " : " + student.getComputer().getName());   
43.            
44.            
45.         //delete   
46. //      Student student = (Student)session.load(Student.class, new Integer(1));   
47. //      session.delete(student);   
48. //      session.beginTransaction().commit();   
49.            
50.         /**  
51.          执行的sql为：  
52.     Hibernate: select student0_.id as id0_1_, student0_.name as name0_1_, computer1_.id as id1_0_, computer1_.name as name1_0_, computer1_.student_id as student3_1_0_ from onetoone.student student0_ left outer join onetoone.computer computer1_ on student0_.id=computer1_.student_id where student0_.id=?  
53.     Hibernate: delete from onetoone.computer where id=?  
54.     Hibernate: delete from onetoone.student where id=?  
55.          */  
56.            
57.            
58.         session.close();   
59.     }   
60.   
61. }  

package com.domain;

import org.hibernate.Query;
import org.hibernate.Session;

import com.util.HibernateSessionFactory;

public class Test {
	
	public static void main(String[] args){
		Session session = HibernateSessionFactory.getSession();
		
		//save
		Student student = new Student();
		student.setName("student9");
		
		Computer computer = new Computer();
		computer.setName("Intel 9");
		
		//computer.setStudent(student)和student.setComputer(computer);都必须要
		computer.setStudent(student);
		student.setComputer(computer);
		
		session.save(student);
		
		/**
		 执行的sql:
		 Hibernate: insert into onetoone.student (name) values (?)
		 Hibernate: insert into onetoone.computer (name, student_id) values (?, ?)
		 */
		
//		
		session.beginTransaction().commit();
		
		//query
		
//		String hql = "from Student where name=?";
//		Query query = session.createQuery(hql);
//		query.setString(0, "student3");
//		
//		Student student = (Student)query.uniqueResult();
//		System.out.println(student.getId() + " : " + student.getComputer().getName());
		
		
		//delete
//		Student student = (Student)session.load(Student.class, new Integer(1));
//		session.delete(student);
//		session.beginTransaction().commit();
		
		/**
		 执行的sql为：
	Hibernate: select student0_.id as id0_1_, student0_.name as name0_1_, computer1_.id as id1_0_, computer1_.name as name1_0_, computer1_.student_id as student3_1_0_ from onetoone.student student0_ left outer join onetoone.computer computer1_ on student0_.id=computer1_.student_id where student0_.id=?
	Hibernate: delete from onetoone.computer where id=?
	Hibernate: delete from onetoone.student where id=?
		 */
		
		
		session.close();
	}

}

2.通过主键方式实现(一个表的主键由另一个表的主键决定)，在这里Computer的主键由Student的主键决定。
Student.hbm.xml:

Java代码

1. <?xml version="1.0" encoding="utf-8"?>   
2. <!DOCTYPE hibernate-mapping PUBLIC "-//Hibernate/Hibernate Mapping DTD 3.0//EN"  
3. "http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd">   
4.   
5. <hibernate-mapping>   
6.     <class name="com.domain.Student" table="student" catalog="onetoone">   
7.         <id name="id" type="java.lang.Integer">   
8.             <column name="id" />   
9.             <generator class="native" />   
10.         </id>   
11.         <property name="name" type="java.lang.String">   
12.             <column name="name" not-null="true" />   
13.         </property>   
14.         <!-- class可以不写，因为根据name的值computer(属性)，会通过反射自动找到属于哪个类的    
15.         <one-to-one cascade="delete,save-update" name="computer" class="com.domain.Computer" property-ref="student"></one-to-one>   
16.         -->   
17.         <one-to-one name="computer"/>   
18.     </class>   
19. </hibernate-mapping>  

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

<hibernate-mapping>
    <class name="com.domain.Student" table="student" catalog="onetoone">
        <id name="id" type="java.lang.Integer">
            <column name="id" />
            <generator class="native" />
        </id>
        <property name="name" type="java.lang.String">
            <column name="name" not-null="true" />
        </property>
        <!-- class可以不写，因为根据name的值computer(属性)，会通过反射自动找到属于哪个类的 
        <one-to-one cascade="delete,save-update" name="computer" class="com.domain.Computer" property-ref="student"></one-to-one>
    	-->
    	<one-to-one name="computer"/>
    </class>
</hibernate-mapping>

Comuter.hbm.xml:

Java代码

1. <?xml version="1.0" encoding="utf-8"?>   
2. <!DOCTYPE hibernate-mapping PUBLIC "-//Hibernate/Hibernate Mapping DTD 3.0//EN"  
3. "http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd">   
4.   
5. <hibernate-mapping>   
6.     <class name="com.domain.Computer" table="computer" catalog="onetoone">   
7.         <id name="id" type="java.lang.Integer">   
8.             <column name="id" />   
9.             <!--generator class="native" /-->   
10.                
11.             <!--Computer的主键由Student的主键决定，可以看成是外键-->   
12.             <generator class="foreign">   
13.                 <param name="property">student</param>   
14.             </generator>   
15.         </id>   
16.           
17.         <property name="name" type="java.lang.String">   
18.             <column name="name" not-null="true" />   
19.         </property>   
20.            
21.          <!-- many开头的是代表该表持有外键   
22.         <many-to-one  name="student" class="com.domain.Student"  unique="true">   
23.             <column name="student_id" />   
24.         </many-to-one> -->   
25.         <one-to-one name="student"/>   
26.     </class>   
27. </hibernate-mapping>  

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

<hibernate-mapping>
    <class name="com.domain.Computer" table="computer" catalog="onetoone">
        <id name="id" type="java.lang.Integer">
            <column name="id" />
            <!--generator class="native" /-->
            
            <!--Computer的主键由Student的主键决定，可以看成是外键-->
            <generator class="foreign">
            	<param name="property">student</param>
            </generator>
        </id>
       
        <property name="name" type="java.lang.String">
            <column name="name" not-null="true" />
        </property>
        
         <!-- many开头的是代表该表持有外键
        <many-to-one  name="student" class="com.domain.Student"  unique="true">
            <column name="student_id" />
        </many-to-one> -->
        <one-to-one name="student"/>
    </class>
</hibernate-mapping>

TestMainKey.java:

Java代码

1. package com.domain;   
2.   
3. import org.hibernate.Session;   
4.   
5. import com.util.HibernateSessionFactory;   
6.   
7. public class TestMainKey {   
8.   
9.     public static void main(String[] args){   
10.         Session session = HibernateSessionFactory.getSession();   
11.            
12.         //save   
13.         Student student = new Student();   
14.         student.setName("student15");   
15.            
16.         Computer computer = new Computer();   
17.         computer.setName("Intel 15");   
18.            
19.            
20.         computer.setStudent(student);   
21. //      student.setComputer(computer);   
22.         //因为save 2个表，所以不需要双向赋值   
23.         session.save(student);   
24.         session.save(computer);   
25.            
26.         session.beginTransaction().commit();   
27.         session.close();   
28.     }   
29. }  

package com.domain;

import org.hibernate.Session;

import com.util.HibernateSessionFactory;

public class TestMainKey {

	public static void main(String[] args){
		Session session = HibernateSessionFactory.getSession();
		
		//save
		Student student = new Student();
		student.setName("student15");
		
		Computer computer = new Computer();
		computer.setName("Intel 15");
		
		
		computer.setStudent(student);
//		student.setComputer(computer);
		//因为save 2个表，所以不需要双向赋值
		session.save(student);
		session.save(computer);
		
		session.beginTransaction().commit();
		session.close();
	}
}

3.通过关系表实现：

Java代码

1. DROP TABLE IF EXISTS `st`;   
2. create table stu_com(   
3.     stu_id int not null,   
4.     com_id int not null  
5. )ENGINE=InnoDB DEFAULT CHARSET=utf8;  

DROP TABLE IF EXISTS `st`;
create table stu_com(
	stu_id int not null,
	com_id int not null
)ENGINE=InnoDB DEFAULT CHARSET=utf8;

Java代码

1. <!--optional="true"的意思是只有当stu_id 和 com_id 都不为空时才在关系表里插入。这样也会插入   
2.   
3. 2遍，所以需要inverse="true"把一方设置为虚的。即不让插入到关系表中-->   
4. <join table="stu-com" optional="true" inverse="true">   
5.     <key column="com_id"/>   
6.     <many-to-one name="student" column="stu_id" unique="true"/>   
7. </join>  

<!--optional="true"的意思是只有当stu_id 和 com_id 都不为空时才在关系表里插入。这样也会插入

2遍，所以需要inverse="true"把一方设置为虚的。即不让插入到关系表中-->
<join table="stu-com" optional="true" inverse="true">
	<key column="com_id"/>
	<many-to-one name="student" column="stu_id" unique="true"/>
</join>