<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE hibernate-mapping PUBLIC "-//Hibernate/Hibernate Mapping DTD 3.0//EN"
   "http://www.hibernate.org/dtd/hibernate-mapping-3.0.dtd" >
<hibernate-mapping package="org.hibernate.test" default-access="field">
   <class entity-name="TestWorkflowItem" name="WorkflowItem2" table="test_workflowitem">
      <id name="id" type="long">
         <generator class="native"/>
      </id>      
      <property name="name" column="name" not-null="true" type="string"/>
       
        <list name="childs" table="test_workflowitem_childs" cascade="all" access="field" lazy="false">
            <key column="item" foreign-key="fk_workflowitem"/>
            <index column="display_order"/>         
            <many-to-many column="child" entity-name="TestWorkflowItem" unique="true" foreign-key="fk_workflowitem_childs" lazy="false"/>                 
        </list>
   </class>
</hibernate-mapping>

package org.hibernate.test;

import java.util.List;

public final class WorkflowItem2 {
    private static final long serialVersionUID = 1L;

    private Long id;

    private String name;
    private List<WorkflowItem2> childs;
    public WorkflowItem2() {
    }

    public void setChilds(List<WorkflowItem2> newChilds) {
        childs = newChilds;
    }

    public List<WorkflowItem2> getChilds() {
        return childs;
    }
    public String getName() {
        return name;
    }
    public void setName(String newName) {
        name = newName;
    }
}

    create table test_workflowitem (
        id bigint not null,
        name varchar(255) not null,
        primary key (id)
    )
    create table test_workflowitem_childs (
        item bigint not null,
        child bigint not null,
        display_order integer not null,
        primary key (item, display_order)
    )
    alter table test_workflowitem_childs
        add constraint UK_ojsoe2oi4ydfh13jnq8cv1k3 unique (child)

    alter table test_workflowitem_childs
        add constraint fk_workflowitem_childs
        foreign key (child)
        references test_workflowitem

    alter table test_workflowitem_childs
        add constraint fk_workflowitem
        foreign key (item)
        references test_workflowitem

    create table test_workflowitem (
        id bigint not null,
        name varchar(255) not null,
        primary key (id)
    )
    create table test_workflowitem_childs (
        item bigint not null,
        display_order integer not null,
        child bigint not null,
        primary key (item, display_order)
    )
    alter table test_workflowitem_childs
        add constraint fk_workflowitem_childs
        foreign key (child)
        references test_workflowitem

    alter table test_workflowitem_childs
        add constraint fk_workflowitem
        foreign key (item)
        references test_workflowitem