hibernate中one-to-one两种配置方式

灰太狼 2022-07-16 09:08 229阅读 0赞

public class Person {  
        private int id;  
        private String name;  
        private IdCard idCard;  
      
        public Person() {  
        }  
      
        public Person(int id, String name, IdCard idCard) {  
            this.id = id;  
            this.name = name;  
            this.idCard = idCard;  
        }  
      
        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 IdCard getIdCard() {  
            return idCard;  
        }  
      
        public void setIdCard(IdCard idCard) {  
            this.idCard = idCard;  
        }  
      
    }  
    
    [java] view plain copy
    public class IdCard {  
        private int id;  
        private Date usefullLife;  
        private Person person;  
      
        public IdCard() {  
        }  
      
        public IdCard(int id, Date usefullLife, Person person) {  
            this.id = id;  
            this.usefullLife = usefullLife;  
            this.person = person;  
        }  
      
        public int getId() {  
            return id;  
        }  
      
        public void setId(int id) {  
            this.id = id;  
        }  
      
        public Date getUsefullLife() {  
            return usefullLife;  
        }  
      
        public void setUsefullLife(Date usefullLife) {  
            this.usefullLife = usefullLife;  
        }  
      
        public Person getPerson() {  
            return person;  
        }  
      
        public void setPerson(Person person) {  
            this.person = person;  
        }  
      
    }

one-to-one方式一：

![Center][]

IdCard.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.huawei.domain.IdCard" table="id_card">  
            <id name="id" type="java.lang.Integer">  
                <column name="id" />  
                <generator class="foreign" >  
                    <param name="property">person</param>  
                </generator>  
            </id>  
              
            <property name="usefullLife" type="java.util.Date">  
                <column name="usefull_life"/>  
            </property>  
              
            <one-to-one name="person" constrained="true"></one-to-one>  
        </class>  
    </hibernate-mapping>

Person.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.huawei.domain.Person">  
            <id name="id" type="java.lang.Integer">  
                <column name="id" />  
                <generator class="native" />  
            </id>  
              
            <property name="name" type="java.lang.String">  
                <column name="name" length="5" not-null="false" />  
            </property>  
              
            <one-to-one name="idCard"></one-to-one>  
        </class>  
    </hibernate-mapping>

one-to-one方式二：

![Center 1][]  
IdCard.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.huawei.domain.IdCard" table="id_card">  
            <id name="id" type="java.lang.Integer">  
              
             <column name="id" />  
             <generator class="native" />  
            </id>  
              
            <property name="usefullLife" type="java.util.Date">  
                <column name="usefull_life"/>  
            </property>  
              
      
            <many-to-one name="person" column="person_id" unique="true"></many-to-one>  
        </class>  
    </hibernate-mapping>

Person.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.huawei.domain.Person">  
            <id name="id" type="java.lang.Integer">  
                <column name="id" />  
                <generator class="native" />  
            </id>  
              
            <property name="name" type="java.lang.String">  
                <column name="name" length="5" not-null="false" />  
            </property>  
              
            <one-to-one name="idCard" property-ref="person"></one-to-one>  
        </class>  
    </hibernate-mapping>

测试：

Session s = null;  
            try{  
                s = HibernateSessionFactory.getSession();  
    //          Person person = (Person)s.get(Person.class, id);  
    //          System.out.println(person.getIdCard().getUsefullLife());  
                  
                IdCard idCard = (IdCard)s.get(IdCard.class, id);  
                System.out.println(idCard.getPerson().getName());  
                  
            } catch (HibernateException e) {  
                e.printStackTrace();  
            }

[Center]: /images/20220716/26335a94f29f47c4a718722cdf83a637.png
[Center 1]: /images/20220716/edc861c3c3a34cb6986afa291e6643a5.png