hibernate OneToOne(Annotation)

 package com.hibernate_onetoonepk;

import javax.persistence.Entity;
import javax.persistence.Id;
import javax.persistence.OneToOne;
import javax.persistence.Table;

@Entity
@Table(name="t_stu")
public class Students {  //在數據庫表中是主表 id爲主鍵被 sid表中的stuId應用
 
 private String id;
 
 private String name;
 
 private StuID stuid;

 @Id
 public String getId() {
  return id;
 }

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

 public String getName() {
  return name;
 }

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

 @OneToOne(mappedBy="stu")
 public StuID getStuid() {
  return stuid;
 }

 public void setStuid(StuID stuid) {
  this.stuid = stuid;
 }

 
}

 

package com.hibernate_onetoonepk;

import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.Id;
import javax.persistence.JoinColumn;
import javax.persistence.OneToOne;
import javax.persistence.Table;

@Entity
@Table(name="t_sid")
public class StuID {

 private int id;
 
 
 private Students stu;

 @OneToOne
 @JoinColumn(name="stuId")
 public Students getStu() {
  return stu;
 }

 public void setStu(Students stu) {
  this.stu = stu;
 }

 @Id
 @GeneratedValue
 public int getId() {
  return id;
 }

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

}

package com.hibernate_onetoonepk;

import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.hibernate.cfg.AnnotationConfiguration;

public class Test {   //測試

 public static void main(String[] args) {
  
  AnnotationConfiguration af = new AnnotationConfiguration();
  SessionFactory sf = af.configure().buildSessionFactory();
  Session session = sf.openSession();
  session.beginTransaction();
//  StuID id = new StuID();
//  Students stu = new Students();
//  stu.setId("2223");
//  stu.setName("yyy");
//  //id.setId(1);
//  id.setStu(stu);
//  
//  session.save(stu);
//  session.save(id);
  
  Students stu = (Students)session.get(Students.class, "2222");
  System.out.println(stu.getName());
  System.out.println(stu.getStuid().getId());
  session.beginTransaction().commit();
 }

}

//一下爲hibernate.cfg.xml的配置

<!DOCTYPE hibernate-configuration PUBLIC
 "-//Hibernate/Hibernate Configuration DTD 3.0//EN"
 "http://hibernate.sourceforge.net/hibernate-configuration-3.0.dtd">

<hibernate-configuration>
 <session-factory>
  <property name="connection.driver_class">com.mysql.jdbc.Driver</property>
  <property name="connection.url">jdbc:mysql://localhost:3306/test?useUnicode=true&amp;characterEncoding=utf8</property>
  <property name="connection.username">root</property>
  <property name="connection.password">123</property>
  <property name="show_sql">true</property>
  <property name="dialect">org.hibernate.dialect.MySQLDialect</property>
  <!-- <mapping resource="com/hibernate/po/User.hbm.xml"/>  -->
  <mapping class="com.hibernate_onetoonepk.Students"></mapping>
  <mapping class="com.hibernate_onetoonepk.StuID"></mapping>
 </session-factory>
</hibernate-configuration>