一对一双向外键关联（annotation方式）

一。annotation方式

package org.hibernate.tutorial.domain;

import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.Id;
import javax.persistence.JoinColumn;
import javax.persistence.OneToOne;
@Entity
public class Husband {
	private int id;
	private String name;
	private Wife wife;
	@Id
	@GeneratedValue
	public int getId() {
		return id;
	}
	public String getName() {
		return name;
	}
	@OneToOne
	@JoinColumn(name="wifeId")
	public Wife getWife() {
		return wife;
	}
	public void setId(int id) {
		this.id = id;
	}
	public void setName(String name) {
		this.name = name;
	}
	public void setWife(Wife wife) {
		this.wife = wife;
	}
	
}

package org.hibernate.tutorial.domain;

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

@Entity
public class Wife {
	private int id;
	private String name;
	private Husband husband;
	
	@Id
	@GeneratedValue
	public int getId() {
		return id;
	}
	public String getName() {
		return name;
	}
	public void setId(int id) {
		this.id = id;
	}
	public void setName(String name) {
		this.name = name;
	}
	@OneToOne(mappedBy="wife")
	public Husband getHusband() {
		return husband;
	}
	public void setHusband(Husband husband) {
		this.husband = husband;
	}
	
}

hibernate.hb.xml
 

<?xml version='1.0' encoding='utf-8'?>
<!DOCTYPE hibernate-configuration PUBLIC
        "-//Hibernate/Hibernate Configuration DTD 3.0//EN"
        "http://www.hibernate.org/dtd/hibernate-configuration-3.0.dtd">

<hibernate-configuration>

    <session-factory>

        <!-- Database connection settings -->
        <property name="connection.driver_class">com.mysql.jdbc.Driver</property>
        <property name="connection.url">jdbc:mysql://localhost/test?useUnicode=true&amp;characterEncoding=utf8</property>
        
        <property name="connection.username">root</property>
        <property name="connection.password">admin</property>

        <!-- JDBC connection pool (use the built-in) -->
        <!--<property name="connection.pool_size">1</property>-->

        <!-- SQL dialect -->
        <property name="dialect">org.hibernate.dialect.MySQLDialect</property>

        <!-- Enable Hibernate's automatic session context management -->
        <property name="current_session_context_class">thread</property>

        <!-- Disable the second-level cache  -->
        <property name="cache.provider_class">org.hibernate.cache.internal.NoCacheProvider</property>

        <!-- Echo all executed SQL to stdout -->
        <property name="show_sql">true</property>
		<property name="format_sql">true</property>
		
        <!-- Drop and re-create the database schema on startup 
        <property name="hbm2ddl.auto">update</property>-->

		<!-- 
		<mapping class="org.hibernate.tutorial.domain.Wife"/> 
		<mapping resource="org/hibernate/tutorial/domain/Husband.hbm.xml"/>
		-->
		<mapping class="org.hibernate.tutorial.domain.Husband"/>
		<mapping class="org.hibernate.tutorial.domain.Wife"/>
    </session-factory>
    
    

</hibernate-configuration>

测试

package com.test;

import org.hibernate.cfg.AnnotationConfiguration;
import org.hibernate.tool.hbm2ddl.SchemaExport;


public class OneToOneORMappingTest {
	public static void main(String[] args) {
		new SchemaExport(new AnnotationConfiguration().configure("/hibernate.cfg.xml")).create(true, false);
	}
}

解释：  @OneToOne(mappedBy="wife") 是设置以对方为主导生成外键，只在对方表生成外键列。是当前类对象Wife的husband属性中wife属性