9.hibernate的一对一映射

一、hibernate的一对一按照外键映射

1.创建如下sql脚本：

 --员工账号表
 create table USERS1
 (
   USERID   NUMBER(6) not null,
   USERNAME VARCHAR2(20),
   USERPASS VARCHAR2(20)
 )
 ;

 --档案表
 create table RESUME1
 (
   RESID     NUMBER(6) not null,
   RESUSERID NUMBER(6),
   RESNAME   VARCHAR2(20),
   RESCARDNO VARCHAR2(20)
 )
 ;

 alter table USERS1
   add constraint PK_USERS1_USERID primary key (USERID);

 alter table RESUME1
   add constraint PK_RESUME1_RESID primary key (RESID);
 alter table RESUME1
   add constraint FK_RESUME1_RESUSERID foreign key (RESUSERID)
   references USERS1 (USERID);

fk_one_to_one_.sql

2.创建如下web项目结构

3.在项目的src根目录下创建主配置文件hibernate.cfg.xml

 <?xml version="1.0" encoding="UTF-8"?>
 <!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">oracle.jdbc.driver.OracleDriver</property>
      <property name="connection.url">jdbc:oracle:thin:@127.0.0.1:1521:orcl</property>
      <property name="connection.username">holly</property>
      <property name="connection.password">sys</property>
      <property name="dialect">org.hibernate.dialect.Oracle10gDialect</property>
      <property name="show_sql">true</property>
      <property name="format_sql">true</property>

      <mapping resource="com/entity/Resume1.hbm.xml"/>
      <mapping resource="com/entity/Users1.hbm.xml"/>
   </session-factory>
 </hibernate-configuration>

hibernate.cfg.xml

4.在项目的src的com.entity包下创建Users1.java类

 package com.entity;

 import java.util.HashSet;
 import java.util.Set;
 /**
  * 员工账号表
  * @author Dell
  *
  */
 public class Users1 {
     private Integer userid;  //员工账号id
     private String username;  //员工姓名
     private String userpass; //员工账号密码
     private Resume1 resume1;  //档案对象

     public Users1() {
     }
     public Users1(Integer userid, String username, String userpass) {
         this.userid = userid;
         this.username = username;
         this.userpass = userpass;
     }
     public Users1(Integer userid, String username, String userpass,
             Resume1 resume1) {
         this.userid = userid;
         this.username = username;
         this.userpass = userpass;
         this.resume1 = resume1;
     }
     public Integer getUserid() {
         return userid;
     }
     public void setUserid(Integer userid) {
         this.userid = userid;
     }
     public String getUsername() {
         return username;
     }
     public void setUsername(String username) {
         this.username = username;
     }
     public String getUserpass() {
         return userpass;
     }
     public void setUserpass(String userpass) {
         this.userpass = userpass;
     }

     public Resume1 getResume1() {
         return resume1;
     }
     public void setResume1(Resume1 resume1) {
         this.resume1 = resume1;
     }
     @Override
     public String toString() {
         return "Users1 [resume1=" + resume1 + ", userid=" + userid
                 + ", username=" + username + ", userpass=" + userpass + "]";
     }

 }

Users1.java

5.在项目的src的com.entity包下创建Users1.hbm.xml

 <?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.entity.Users1" table="USERS1" schema="HOLLY" >
       <id name="userid" type="java.lang.Integer" column="USERID">
          <generator class="assigned"/>
       </id>
       <property name="username" type="java.lang.String" column="USERNAME"/>
       <property name="userpass" type="java.lang.String" column="USERPASS"/>

       <!-- 多对一映射：name是emp中外键字段引用的对象，class是对象的类型，column是数据库中对应的外键列字段名 -->
       <one-to-one name="resume1" class="com.entity.Resume1" property-ref="users1"/>
    </class>
 </hibernate-mapping>

Users1.hbm.xml

6.在项目的src的com.entity包下创建Resume1.java类

 package com.entity;

 import java.util.Date;
 /**
  * 档案表
  * @author Dell
  *
  */
 public class Resume1 {
     private Integer resid; //档案编号
     private Users1 users1;  //用户对象
     private String resname;  //档案名称
     private String rescardno; //档案卡号

     public Resume1() {
     }

     public Resume1(Integer resid, String resname, String rescardno) {
         this.resid = resid;
         this.resname = resname;
         this.rescardno = rescardno;
     }

     public Resume1(Integer resid, Users1 users1, String resname,
             String rescardno) {
         this.resid = resid;
         this.users1 = users1;
         this.resname = resname;
         this.rescardno = rescardno;
     }

     public Integer getResid() {
         return resid;
     }

     public void setResid(Integer resid) {
         this.resid = resid;
     }

     public Users1 getUsers1() {
         return users1;
     }

     public void setUsers1(Users1 users1) {
         this.users1 = users1;
     }

     public String getResname() {
         return resname;
     }

     public void setResname(String resname) {
         this.resname = resname;
     }

     public String getRescardno() {
         return rescardno;
     }

     public void setRescardno(String rescardno) {
         this.rescardno = rescardno;
     }

     @Override
     public String toString() {
         return "Resume1 [rescardno=" + rescardno + ", resid=" + resid
                 + ", resname=" + resname + ", users1=" + users1 + "]";
     }

 }

Resume1.java

7.在项目的src的com.entity包下创建Resume1.hbm.xml

 <?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.entity.Resume1" table="RESUME1" schema="holly">
   <!-- 主键配置 -->
    <id name="resid" type="java.lang.Integer" column="RESID">
       <!-- 主键由应用程序负责生成 -->
       <generator class="assigned"/>
    </id>
    <!-- 部门名称 -->
    <property name="resname" type="java.lang.String" column="RESNAME"/>

    <!-- 部门位置 -->
    <property name="rescardno" type="java.lang.String" column="RESCARDNO"/>
    <!-- 一个个档案对应一个人 -->
    <!-- unique表示唯一约束，确保用户唯一 unique=true表示一一对应 -->
   <many-to-one name="users1" class="com.entity.Users1" column="RESUSERID" cascade="all" unique="true"/>
 </class>
 </hibernate-mapping>

Resume1.hbm.xml

8.在项目的src的ccom.util包下创建HibernateUtil.java

 package com.util;

 import org.hibernate.HibernateException;
 import org.hibernate.Session;
 import org.hibernate.SessionFactory;
 import org.hibernate.cfg.Configuration;

 public class HibernateUtil {
     /**
      * 创建线程池来管理Session
      */
     private static ThreadLocal<Session> thread=new ThreadLocal<Session>();
     /**
      * 创建读取配置文件的对象
      */
     private static Configuration config=null;
     /**
      * 创建获取Session的工厂
      */
     private static SessionFactory factory=null;

     /**
      * 读取配置文件
      */
     static{
         try {
             config=new Configuration().configure("/hibernate.cfg.xml");
             factory=config.buildSessionFactory();
         } catch (HibernateException e) {
             System.out.println("读取配置文件或创建SessionFactory失败！");
             e.printStackTrace();
         }
     }

     /**
      * 获取session
      * @return
      */
     public static Session getSession(){
         Session session=thread.get();
         if(session==null){
             session=factory.openSession();
             thread.set(session);
         }
         return session;
     }

     /**
      * 关闭Session
      */
     public static void closeSession(){
         Session session=thread.get();
         thread.set(null);
         session.close();
     }

 }

HibernateUtil.java

9.在项目的src的com.dao包下创建Resume1Dao.java

 package com.dao;

 import java.text.ParseException;
 import java.text.SimpleDateFormat;
 import java.util.Date;
 import java.util.List;
 import java.util.Set;
 import java.util.logging.SimpleFormatter;

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

 import com.entity.Users1;
 import com.entity.Resume1;
 import com.util.HibernateUtil;

 public class Resume1Dao {

     public static void main(String[] args) {
         //saveResume1();
         loadResume1();

     }
     /**
      * 2.立即加载：当查询档案信息时查询账号信息
      *
      */
     private static void loadResume1() {
           Session session=HibernateUtil.getSession();
           Resume1 resume1=(Resume1) session.get(Resume1.class, 1);
           System.out.println("姓名："+resume1.getResname());
           System.out.println("用户名："+resume1.getUsers1().getUsername());

           HibernateUtil.closeSession();

     }
     /**
      * 1.一对一 按照外键映射：级联操作，保存档案信息时，保存员工账号信息
      * 1条查询sql，2条插入sql,查询sql见readme.txt
      */
     private static void saveResume1() {
           Session session=HibernateUtil.getSession();
            Transaction tx=session.beginTransaction();
            //创建员工档案对象
            Resume1 resume1=new Resume1(1, "李四", "2014010101010");

            //创建员工账户信息
            Users1 users1=new Users1(1, "lisi", "123");

            //给员工档案的users1对象赋值
            resume1.setUsers1(users1);

            //给员工账号的resume1对象赋值
            users1.setResume1(resume1);

             //添加员工档案信息时级联保存员工账号信息
             session.save(resume1);
             tx.commit();
             System.out.println("添加成功");

             HibernateUtil.closeSession();

     }

 }

Resume1Dao.java

10.运行结果如下：

 /**
      * 1.一对一 按照外键映射：级联操作，保存档案信息时，保存员工账号信息
      * 1条查询sql，2条插入sql,查询sql见readme.txt
      *
      */
 Hibernate:
     select
         users1x_.USERID,
         users1x_.USERNAME as USERNAME1_,
         users1x_.USERPASS as USERPASS1_
     from
         HOLLY.USERS1 users1x_
     where
         users1x_.USERID=?
 Hibernate:
     insert
     into
         HOLLY.USERS1
         (USERNAME, USERPASS, USERID)
     values
         (?, ?, ?)
 Hibernate:
     insert
     into
         holly.RESUME1
         (RESNAME, RESCARDNO, RESUSERID, RESID)
     values
         (?, ?, ?, ?)
  /**
      * 2.立即加载：当查询档案信息时查询账号信息
      */

 Hibernate:
     select
         resume1x0_.RESID as RESID0_0_,
         resume1x0_.RESNAME as RESNAME0_0_,
         resume1x0_.RESCARDNO as RESCARDNO0_0_,
         resume1x0_.RESUSERID as RESUSERID0_0_
     from
         holly.RESUME1 resume1x0_
     where
         resume1x0_.RESID=?
 姓名：李四
 Hibernate:
     select
         users1x0_.USERID as USERID1_1_,
         users1x0_.USERNAME as USERNAME1_1_,
         users1x0_.USERPASS as USERPASS1_1_,
         resume1x1_.RESID as RESID0_0_,
         resume1x1_.RESNAME as RESNAME0_0_,
         resume1x1_.RESCARDNO as RESCARDNO0_0_,
         resume1x1_.RESUSERID as RESUSERID0_0_
     from
         HOLLY.USERS1 users1x0_
     left outer join
         holly.RESUME1 resume1x1_
             on users1x0_.USERID=resume1x1_.RESUSERID
     where
         users1x0_.USERID=?
 Hibernate:
     select
         resume1x0_.RESID as RESID0_0_,
         resume1x0_.RESNAME as RESNAME0_0_,
         resume1x0_.RESCARDNO as RESCARDNO0_0_,
         resume1x0_.RESUSERID as RESUSERID0_0_
     from
         holly.RESUME1 resume1x0_
     where
         resume1x0_.RESUSERID=?
 用户名：lisi
      

readme.txt

二、Hibernate一对一按照主键查询

1.创建如下sql语句

 create table RESUME2
 (
   RESID     NUMBER(6) not null,
   RESNAME   VARCHAR2(20),
   RESCARDNO VARCHAR2(20)
 )
 ;

 create table USERS2
 (
   USERID   NUMBER(6) not null,
   USERNAME VARCHAR2(20) not null,
   USERPASS VARCHAR2(20) not null
 )
 ;

 alter table RESUME2
   add constraint PK_RESUME2_RESID primary key (RESID);

 alter table USERS2
   add constraint PK_USERS2_USERID primary key (USERID)
   disable;
 alter table USERS2
   add constraint FK_USERS2_USERID foreign key (USERID)
   references RESUME2 (RESID);

pk_one_to_one_.sql

2.项目的主配置，工具类，实体类都和上面一样，此处省略

3.在com.entity包下编辑Users2.hbm.xml映射文件

 <?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.pojo.Users2" table="USERS2">
   <id name="usersid" type="java.lang.Integer" column="USERSID">
     <!-- 双向一对一:按照外键关联映射配置 -->
     <generator class="foreign">
       <!-- 当前类User2外键列所关联的另一方Resume2类的对象属性名resume2 -->
        <param name="property">resume2</param>
     </generator>
   </id>
   <property name="usersname" type="java.lang.String" column="USERSNAME"/>
   <property name="userspwd" type="java.lang.String" column="USERSPWD"/>

   <!-- 当前users2表中的usersid列又作为主键,又作为外键 -->
   <one-to-one name="resume2" class="com.pojo.Resume2"
   constrained="true" cascade="all"/>
 </class>
 </hibernate-mapping>

Users2.hbm.xml

4.在com.entity包下编辑Resume2.hbm.xml映射文件

 <?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.pojo.Resume2" table="RESUME2">
   <id name="resid" type="java.lang.Integer" column="RESID">
     <generator class="assigned"/>
   </id>
   <property name="resname" type="java.lang.String" column="RESNAME"/>
   <property name="rescard" type="java.lang.String" column="RESCARD"/>

   <one-to-one name="users2" class="com.pojo.Users2"/> 

 </class>
 </hibernate-mapping>

Resume2.hbm.xml

5.在com.dao包下创建Test.java

 package com.test;

 import org.hibernate.Session;

 import com.pojo.Resume2;
 import com.pojo.Users2;
 import com.util.HibernateUtil;

 public class Test {
     public static void main(String[] args) {
          //1.级联添加操作
          //saveResumeToUsers();
          //2.根据主键查询
          loadResume();

     }
     /**
      * 1.级联添加操作
 Hibernate: select resume2x_.RESID, resume2x_.RESNAME as RESNAME0_, resume2x_.RESCARD as RESCARD0_ from RESUME2 resume2x_ where resume2x_.RESID=?
 Hibernate: insert into RESUME2 (RESNAME, RESCARD, RESID) values (?, ?, ?)
 Hibernate: insert into USERS2 (USERSNAME, USERSPWD, USERSID) values (?, ?, ?)
      */
     private static void saveResumeToUsers() {
         //1.获取session对象
         Session session=HibernateUtil.getSession();

         //2.创建瞬时对象
         Users2 users1=new Users2(3, "倩倩", "123");
         Resume2 resume1=new Resume2(3, "倩倩档案", "qianqian320112");

         users1.setResume2(resume1);
         resume1.setUsers2(users1);

         //3.级联添加
         session.save(users1);

         session.beginTransaction().commit();
         //4.提交事务
         System.out.println("save cascade success...");
     }
     /**
 Hibernate: select resume2x0_.RESID as RESID0_1_, resume2x0_.RESNAME as RESNAME0_1_, resume2x0_.RESCARD as RESCARD0_1_, users2x1_.USERSID as USERSID1_0_, users2x1_.USERSNAME as USERSNAME1_0_, users2x1_.USERSPWD as USERSPWD1_0_ from RESUME2 resume2x0_ left outer join USERS2 users2x1_ on resume2x0_.RESID=users2x1_.USERSID where resume2x0_.RESID=?
 Resume2 [rescard=qianqian320112, resid=3, resname=倩倩档案]
 Users2 [usersid=3, usersname=倩倩, userspwd=123]
      */
     private static void loadResume() {
         //1.获取session对象
         Session session=HibernateUtil.getSession();

         //2.根据主键去查询
         //不会出现sql,xml默认就是延时记载
         Resume2 resume1=(Resume2) session.load(Resume2.class, 3);
         System.out.println(resume1);
         System.out.println(resume1.getUsers2());

     }

 }

Test.java

6.运行结果如下