Hibernate多对一自身关联

drop table if exists part;

-- alter table part drop foreign key fk_part;

create table part(
id bigint not null primary key,
name varchar(20),
father_id bigint
);

alter table part add index fk_part (father_id),
add constraint fk_part foreign key (father_id) references part(id);

#[WinMySQLAdmin]
#Server=D:/mysql-5.0.37-win32/bin/mysqld.exe

[mysqld]
# set basedir to your installation path
#basedir=D:/mysql-5.0.37-win32
# set datadir to the location of your data directory
port = 3306
key_buffer = 16K
max_allowed_packet = 1M
table_cache = 4
sort_buffer_size = 64K
read_buffer_size = 256K
read_rnd_buffer_size = 256K
net_buffer_length = 2K
thread_stack = 64K
datadir=data
default-character-set=gbk
init_connect='SET AUTOCOMMIT=0'
default-table-type=InnoDB
init_connect='set completion_type=1'


default-character-set=gbk

public class Part implements java.io.Serializable {

    // Fields

    private Long id;
    private String name;
    private Part part;  //父Part
    private Set parts = new HashSet(0); //字Part

    // Constructors

    /** default constructor */
    public Part() {
    }

    /** minimal constructor */
    public Part(Long id) {
        this.id = id;
    }

    public Part(String name) {
        this.name = name;
    }  
    
    /** full constructor */
    public Part(Long id, Part part, String name, Set parts) {
        this.id = id;
        this.part = part;
        this.name = name;
        this.parts = parts;
    }

    // Property accessors

    public Long getId() {
        return this.id;
    }

    public void setId(Long id) {
        this.id = id;
    }

    public Part getPart() {
        return this.part;
    }

    public void setPart(Part part) {
        this.part = part;
    }

    public String getName() {
        return this.name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public Set getParts() {
        return this.parts;
    }

    public void setParts(Set parts) {
        this.parts = parts;
    }

}

<?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="org.lavasoft.Part" table="part">
        <id name="id" type="java.lang.Long">
            <column name="id" />
            <generator class="increment" />
        </id>
        <property name="name" type="java.lang.String">
            <column name="name" length="20" />
        </property>
        <many-to-one name="part" class="org.lavasoft.Part" fetch="select">
            <column name="father_id" />
        </many-to-one>
        <set name="parts" cascade="save-update" inverse="true">
            <key>
                <column name="father_id" />
            </key>
            <one-to-many class="org.lavasoft.Part" />
        </set>
    </class>
</hibernate-mapping>

package org.lavasoft;

import org.hibernate.HibernateException;
import org.hibernate.Session;
import org.hibernate.Transaction;

public class Test {

    /**
     * @param args
     */
    public static void main(String[] args) {
        // TODO Auto-generated method stub
        //if(HibernateSessionFactory.getSession()==null) System.out.println("null");
        
        Part p1=new Part("p1");
        Part p11=new Part("p11");
        Part p12=new Part("p12");
    
        p1.getParts().add(p11);
        p1.getParts().add(p12);
        p11.setPart(p1);
        p12.setPart(p1);
        
        Session session = HibernateSessionFactory.getSession();
        Transaction tx=session.beginTransaction();
        
        try {
            session.save(p1);
            tx.commit();
        } catch (HibernateException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
            tx.rollback();
        }finally{
            session.close();
        }      
    }
}