Hello:

Please, need your help. I have

Teacher ---many-to-many --- Course

then, I did create a new entity (intermediate), because I have properties in the relation, This intermediate entity is TeacherCourse, then

Teacher ---one-to-many ---TeacherCourse
TeacherCourse --- many-to-one Course

My problem is:

I have 5 courses in DB, (a,b,c,d,e), and I have 2 teachers (F and G).
F to teach a,b,c
G to teach d, e

it's work fine, but if I attempt give other course for G, and this course belong F, it's don't work. Back to front is the same, I can't give to F a G's course.

I use set. Bag is the solution??? Other???

Please Help me

Hibernate version: Hibernate 3.1.3

Mapping documents:

This is TeacherCourse

<?xml version="1.0"?>
<!DOCTYPE hibernate-mapping PUBLIC
"-//Hibernate/Hibernate Mapping DTD 3.0//EN"
"http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd">
<hibernate-mapping>
<class name="encuestas.TeacherCourse" table="TEACHER_COURSE">

<id name="id" type="long" column="ID">
<!-- <meta attribute="finder-method">findByID</meta> -->
<generator class="native"/>
</id>

<property name="semestre_dicta"
type="string"
not-null="true"
update="false">
<column name="SEMESTRE_DICTA"/>
</property>

<many-to-one
name="teacher"
class="encuestas.Persona">
<column name="teacherID" not-null="true" />
</many-to-one>

<many-to-one
name="course"
class="encuestas.Course"
>
<column name="courseID" not-null="true" />
</many-to-one>
</class>
</hibernate-mapping>

Course:

<?xml version="1.0"?>
<!DOCTYPE hibernate-mapping PUBLIC
"-//Hibernate/Hibernate Mapping DTD 3.0//EN"
"http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd">
<hibernate-mapping>
<class name="encuestas.Course" table="COURSE">

<id name="id" type="long" column="ID">
<!-- <meta attribute="finder-method">findByID</meta> -->
<generator class="native"/>
</id>
<property name="nombre"
type="string"
not-null="true">
<column name="NOMBRE"/>
</property>

<set name="Teacher_course"
lazy="true"
inverse="true"
cascade="delete" >
<key>
<column name="courseID" />
</key>
<one-to-many class="encuestas.TeacherCourse"/>
</set>
</class>
</hibernate-mapping>

Teacher, is subclass of Persona
..
<joined-subclass name="encuestas.Teache" table="Teacher">
<key column="Teacher_ID"/>
<property name="tipo"
type="string"
not-null="true">
<column name="TIPO"/>
</property>

<set name="Teacher_course"
lazy="true"
inverse="true"
cascade="delete" >
<key>
<column name="teacherID" />
</key>
<one-to-many class="encuestas.TeacherCourse"/>
</set>

</joined-subclass>
..

Extract for Course

public class Course implements Serializable{

private Long id;
...
private Set Teacher_course = new HashSet();
..
<getter and setter>
---
and TeacherCourse

public class TeacherCourse implements Serializable {
private Long id;
..
private Course course;
private Teacher teache;
<getters and setters>
...

Code between sessionFactory.openSession() and session.close():

Query q = sess.createQuery("from Persona p where p.rut = :rut");
q.setString("rut", rut);
Teacher p = (Teacher) q.uniqueResult();
p.getId();
Course r = (Course) sess.load(Course.class, id_ramo);
TeacherCourse rp = new TeacherCourse();
rp.setSemestre_dicta(sem_act);
rp.setTeacher(p);
rp.setCourse(r);
r.getTeacher_course().add(rp);
p.getTeacher_course().add(rp);
sess.save(rp);



Full stack trace of any exception that occurs:

Name and version of the database you are using:
Mysql 5.0.22-Debian_0ubuntu6.06.2

Please, help me.

The solution is use many-to-many instead of one-to-many in
<set name="Teacher_course"
lazy="true"
inverse="true"
cascade="delete" >
<key>
<column name="teacherID" />
</key>
<one-to-many class="encuestas.TeacherCourse"/>
</set>
and use cascade="all" instead of just delete.
For additonal help use the link http://forum.hibernate.org/viewtopic.ph ... 38#2329653
-Poonam

Thank's, but the mapping in many-to-many don't hold relationship's properties.

Before, I do the mapping with compose element,

<joined-subclass....Teacher>
<set name="courses" lazy="true" table="TEACHER_COURSE">
<key column="teacherID"/>
<composite-element class="encuestas.TeacherCourse">
<parent name="teacher"/>
<many-to-one name="course"
class="encuestas.Course"
column="courseID"
not-null="true"/>
<property name="semestre" column="SEMESTRE" not-null="true"/>
<property name="agno" column="AGNO" not-null="true"/>
<property name="estado" column="ESTADO" not-null="true"/>
</composite-element>
</set> -->


but it's not bidirectional, and I need that.

The problem is: One entity (A) have 2 or more relationship of type many-to-one, with bidirection

A many-to-one B
A many-to-one C

In
A a = new A();
a.setProperty1(prop1);
a.setProperty2(prop2);
a.setOneB(b); //b is un object of type B
a.setOneC(c); //c is un object of type C
b.getThe_As().add(a);--->This Ok
sess.save(a); // it's work fine
out.println("hello1"); ---> ok
c.getThe_As().add(a);------> This don't work, bidirection crash
out.println("hello2"); ---> nothing :(

It's a bug????

Someone of Hibernate Team help me, please!!!