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基于外键的单向1-1关联

一个House关联一个Owner。

House类：

package com.ydoing.hibernate3;import javax.persistence.CascadeType;import javax.persistence.Column;import javax.persistence.Entity;import javax.persistence.GeneratedValue;import javax.persistence.GenerationType;import javax.persistence.Id;import javax.persistence.JoinColumn;import javax.persistence.OneToOne;import javax.persistence.Table;@Entity@Table(name = "house_inf")public class House {
       @Id    @Column(name = "house_id")    @GeneratedValue(strategy = GenerationType.IDENTITY)    private Integer id;    private String name;    @OneToOne(targetEntity = Owner.class, cascade = CascadeType.ALL)    @JoinColumn(name = "owner_id", referencedColumnName = "owner_id", unique = true)    private Owner owner;    public Integer getId() {        return id;    }    public void setId(Integer id) {        this.id = id;    }    public String getName() {        return name;    }    public void setName(String name) {        this.name = name;    }    public Owner getOwner() {        return owner;    }    public void setOwner(Owner owner) {        this.owner = owner;    }}

Owner类：

package com.ydoing.hibernate3;import javax.persistence.Column;import javax.persistence.Entity;import javax.persistence.GeneratedValue;import javax.persistence.GenerationType;import javax.persistence.Id;import javax.persistence.Table;@Entity@Table(name = "owner_inf")public class Owner {
       @Id    @Column(name = "Owner_id")    @GeneratedValue(strategy = GenerationType.IDENTITY)    private Integer id;    public Integer getId() {        return id;    }    public void setId(Integer id) {        this.id = id;    }    public String getName() {        return name;    }    public void setName(String name) {        this.name = name;    }    private String name;}

测试类：

package com.ydoing.hibernate3;import org.hibernate.Session;import org.hibernate.SessionFactory;import org.hibernate.Transaction;import org.hibernate.boot.registry.StandardServiceRegistryBuilder;import org.hibernate.cfg.Configuration;import org.hibernate.service.ServiceRegistry;import org.junit.BeforeClass;import org.junit.Test;public class Main {    private static Session session;    @BeforeClass    public static void init() {        Configuration conf = new Configuration();        conf.configure();        ServiceRegistry serviceRegistry = new StandardServiceRegistryBuilder().applySettings(conf.getProperties())                .build();        SessionFactory factory = conf.buildSessionFactory(serviceRegistry);        session = factory.openSession();    }    @Test    public void test() {        Transaction tx = session.getTransaction();        tx.begin();        Owner owner = new Owner();        owner.setName("Jack");        House house = new House();        house.setName("elegant");        house.setOwner(owner);        session.save(house);        tx.commit();        session.close();    }}

console输出：

Hibernate:     insert     into        owner_inf        (name)     values        (?)Hibernate:     insert     into        house_inf        (name, owner_id)     values        (?, ?)

从输出可以看出owner_id作为house_inf的外键。

数据表：