hibernate中1VS1操作过程

一、 数据库中两个表:

-- 删除表 DROP TABLE idcard ; DROP TABLE person ;   -- 创建表 CREATE TABLE person (        id VARCHAR(32) NOT NULL PRIMARY KEY ,        name VARCHAR(20) NOT NULL ,        age int ) ; CREATE TABLE idcard (        id VARCHAR(32) NOT NULL PRIMARY KEY ,        serial VARCHAR(18) NOT NULL ,        expiry int ) ;

它们是一对一关系：

二、POJO类如下：

package com.wangbass.pojo;   public class Person {    private String id;    private String name;    private Integer age;    private IDCard idCard;       public IDCard getIdCard() {       return idCard;    }    public void setIdCard(IDCard idCard) {       this.idCard = idCard;    }    public Integer getAge() {       return age;    }    public void setAge(Integer age) {       this.age = age;    }    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;    }    }

 

package com.wangbass.pojo;   public class IDCard {    private String id;    private String serial;    private Integer expiry;    private Person person;    public Integer getExpiry() {       return expiry;    }    public void setExpiry(Integer expiry) {       this.expiry = expiry;    }    public String getId() {       return id;    }    public void setId(String id) {       this.id = id;    }    public Person getPerson() {       return person;    }    public void setPerson(Person person) {       this.person = person;    }    public String getSerial() {       return serial;    }    public void setSerial(String serial) {       this.serial = serial;    } }

 

三、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"> <!--     Mapping file autogenerated by MyEclipse Persistence Tools --> <hibernate-mapping>     <class name="com.wangbass.pojo.Person" table="person">         <id name="id" type="java.lang.String">             <column name="id" length="32" />             <generator class="uuid.hex"></generator>         </id>         <property name="name" type="java.lang.String">             <column name="name" length="20" not-null="true" />         </property>         <property name="age" type="java.lang.Integer">             <column name="age" />         </property>         <one-to-one name="idCard" class="com.wangbass.pojo.IDCard"            cascade="all">         </one-to-one>     </class> </hibernate-mapping>

其中的<one-to-one>中的cascade=”all”很关键。

<?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"> <!--    Mapping file autogenerated by MyEclipse Persistence Tools --> <hibernate-mapping>    <class name="com.wangbass.pojo.IDCard" table="idcard">       <id name="id" type="java.lang.String">          <column name="id" length="32" />          <generator class="foreign">             <param name="property">person</param>          </generator>       </id>       <property name="serial" type="java.lang.String">          <column name="serial" length="18" not-null="true" />       </property>       <property name="expiry" type="java.lang.Integer">          <column name="expiry" />       </property>       <one-to-one name="person" class="com.wangbass.pojo.Person"></one-to-one>    </class> </hibernate-mapping>

其中<id name="id" type="java.lang.String">

         <column name="id" length="32" />

         <generator class="foreign">

            <param name="property">person</param>

         </generator>

      </id>

指定与person的外键关联。

四、测试类如下：

package com.wangbass.pojo;   import java.util.List; import org.hibernate.Query; import org.hibernate.Session; import org.hibernate.cfg.Configuration;   public class HibernateDemo01Test {    private Session session;      public HibernateDemo01Test() {       this.session = new Configuration().configure().buildSessionFactory()             .openSession();    }      public void insert(Person p) {       this.session.save(p);       this.session.beginTransaction().commit();    }      public void update(Person p) {       this.session.update(p);       this.session.beginTransaction().commit();    }      public Person queryById(String id) {       Person p = null;       String hql = "FROM Person p WHERE p.id=?";       Query q = this.session.createQuery(hql);       q.setString(0, id);       List l = q.list();       if (l.size() != 0) {          p = (Person) l.get(0);       }         return p;      }      public void delete(Person p) {       this.session.delete(p);       this.session.beginTransaction().commit();    }      public static void main(String[] args) {         HibernateDemo01Test hdt = new HibernateDemo01Test();       /*        * Person p=new Person(); p.setAge(13); p.setName("王权2"); IDCard        * idcard=new IDCard(); idcard.setSerial("2222222222");        * idcard.setExpiry(13); idcard.setPerson(p); p.setIdCard(idcard);        * hdt.insert(p);        */       Person p = hdt.queryById("2c9ab70a20cc9e4c0120cc9e4dd10001");       System.out.println("Person name:" + p.getName());       System.out.println("Person age:" + p.getAge());       /*        * p.setAge(20); IDCard idcard=p.getIdCard(); System.out.println("IDCard        * Expiry:"+idcard.getExpiry()); idcard.setExpiry(20); hdt.update(p);        */       hdt.delete(p);       // TODO Auto-generated method stub    } }

 

这样无论对Person对象进行什么操作，idcard对象就会自动跟着操作，实现目的。