Hibernate 单表实现树结构

　　来看看通过单表来实现一个树形结构的方式。这里假设有这样一个实体名叫儿子，一个儿子只能有一个父亲，而一个父亲可能有多个儿子，因为父亲本身也是他自身父亲的儿子，所以在这里他们的属性没有什么区别。

　　一。Son

package com.aaxis.model;

/**
 * User: Zhong Gang
 */
public class Son {
    private Integer id;
    private Integer version;

    private String name;

    private Son dad;

    public Son() {
    }

    public Son(String name) {
        this.name = name;
    }

    public Son(String name, Son dad) {
        this.name = name;
        this.dad = dad;
    }
}

　　二。hbm映射配置文件

<?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 default-access="field">

    <class name="com.aaxis.model.Son" table="son">
        <id name="id" column="id" type="java.lang.Integer">
            <generator class="native"/>
        </id>
        <version name="version" column="version" type="java.lang.Integer"/>
        <property name="name" column="name" type="java.lang.String" index="person_name"/>

        <many-to-one name="dad" column="dad_id" class="com.aaxis.model.Son"/>
    </class>

</hibernate-mapping>

　　三。测试代码

package com.aaxis;

import com.aaxis.model.Son;
import junit.framework.TestCase;
import org.hibernate.SessionFactory;
import org.hibernate.Transaction;
import org.hibernate.cfg.Configuration;
import org.hibernate.classic.Session;

/**
 * Created by IntelliJ IDEA.
 * User: Zhong Gang
 * Date: 10/24/11
 * Time: 11:50 AM
 */
public class HibernateCoreTest extends TestCase {

    public void testSon() throws Exception {
        Son dad = new Son("dad");

        Son son1 = new Son("son1", dad);
        Son son2 = new Son("son2", dad);
        Son son3 = new Son("son3", dad);

        SessionFactory sessionFactory = new Configuration().configure().buildSessionFactory();
        Session session = sessionFactory.openSession();
        Transaction transaction = session.beginTransaction();
        session.saveOrUpdate(dad);
        session.saveOrUpdate(son1);
        session.saveOrUpdate(son2);
        session.saveOrUpdate(son3);
        transaction.commit();
        session.close();
    }
}

　　四。数据表结构及测试截图

　　 Hibernate 单表实现树结构

　　最后附上源码以供各位参考