many-to-many

tads · **Posted:** Thu May 20, 2004 7:46 am

Hi,

I have the followings tables:

-------------------------------------------
Company:
-------------------------------------------
company_id varchar2(18) PK
name varchar2(50)
-------------------------------------------

-------------------------------------------
User:
-------------------------------------------
user_id varchar2(10) PK
name varchar2(50)
-------------------------------------------

A company can to have more than one contact user and
the user can be contact user of some Company.

So, the following table was created:

-------------------------------------------
company_x_contact_user:
-------------------------------------------
company_id varchar2(18) pk and fk
user_id varchar2(10) pk and FK
other_column varchar2(10)

-------------------------------------------

I can to create a many-to-many relationship, where
Company have a List of user and User have List of company,
but how can I retrieve the other_column????

thanks!!!

[]

anthony · **Posted:** Thu May 20, 2004 9:31 am

your association table is not a simple one since it handle extra info (other column)

you may use composite element

http://www.hibernate.org/hib_docs/refer ... nents.html

tads · **Posted:** Thu May 20, 2004 9:58 am

OK.. thanks!!!

and if the other_column is PK too????

anthony · **Posted:** Thu May 20, 2004 9:59 am

you can add what you want in a component, even many-to-one

tads · **Posted:** Fri May 21, 2004 11:50 am

Hi,

I

anthony · **Posted:** Fri May 21, 2004 12:23 pm

When asking questions, give at least:
the Hibernate version
your mapping documents
the Java code between sessionFactory.openSession() and session.close()
the full stack trace of any exception that occurs
the name and version of the database you are using
a debug level Hibernate log excerpt is also appreciated

tads · **Posted:** Fri May 21, 2004 12:47 pm

OPssss!!!! Ok, ok...

Version Hibernate: 2.0.2
SGDB: Oracle 8.1.7

The mapping files are:

Code:

<!-- User --> 
<hibernate-mapping> 
    <class name="User" table="user"> 
      <id name="cpf" column="cpf"> 
         <generator class="assigned"/> 
      </id>        
        <property name="name" column="nome"/>    
        <bag name="contactCompanies" table="empresa_x_contato" inverse="true" lazy="true"> 
         <key column="cpf_contato"/>          
         <many-to-many class="Company" column="cnpj"/> 
        </bag>        
        <bag name="templates" table="perfil_x_usuario" inverse="true" lazy="false" cascade="save-update"> 
         <key column="cpf"/> 
         <many-to-many class="Template" column="id_perfil"/> 
        </bag>        
    </class> 
</hibernate-mapping> 

<!-- Company --> 

<hibernate-mapping> 
    <class name="Company" table="company"> 
      <id name="cnpj" column="cnpj"> 
         <generator class="assigned"/> 
      </id> 
      <property name="name" column="nome"/> 
        <bag name="templates" inverse="true" lazy="false"> 
         <key column="cnpj"/> 
         <one-to-many class="Template"/> 
        </bag> 
      <bag name="companies" table="empresa_x_empresa" inverse="true" lazy="true"> 
         <key column="cnpj"/> 
         <many-to-many class="Company" column="cnpj"/> 
        </bag>    
      <bag name="companyParents" table="empresa_x_empresa" inverse="true" lazy="false" cascade="save-update"> 
         <key column="cnpj_pai"/> 
         <many-to-many class="Company" column="cnpj"/> 
        </bag> 
      <bag name="contactUsers" table="empresa_x_contato" inverse="true" lazy="false" cascade="save-update"> 
         <key column="cnpj"/> 
         <many-to-many class="User" column="cpf_contato"/> 
        </bag>                
    </class> 

</hibernate-mapping> 


<!-- Template --> 

<hibernate-mapping> 
    <class name="Template" table="template"> 
      <id name="idTemplate" column="id_template"> 
         <generator class="native"> 
            <param name="sequence">seq_template</param> 
         </generator> 
      </id>       
        <property name="name" column="nome"/> 
      <many-to-one name="company" column="cnpj" 
         class="Company"/>          
        <bag name="users" table="perfil_x_usuario" inverse="true" lazy="true"> 
         <key column="id_perfil"/> 
         <many-to-many class="User" column="cpf"/> 
        </bag>                
      <bag name="templates" inverse="true" lazy="true"> 
         <key column="id_perfil_pai"/> 
         <one-to-many class="Template"/> 
        </bag>        
    </class> 

</hibernate-mapping>

The relationship must be:

-An User can to have some Templates and the templates can to have
some Users.
-An User can to have some contactCompany (Company) and Company
can to have some contactUser (Company have some contact users)
-A Company can to have some companyParents (Matrix Company)
an can to have some branch offices (Object Company too).

I try to do this:

Code:

String query = "from User u";
session.createQuery(query); 

And It occurs the following (debug eclipse):

Code:

e=PropertyAccessException
   cause=NullPointerException
   cause=PropertyAccessException
   .
   .
   detailMessage="exception getting property value with CGLIB"
   persistentClass=Class(Company)
   propertyName="?"
   stackTrace=null

I didn