I couldn't find much googling for an answer.
Hibernate supports it in a way similar to JPA but it doesn't require you to have
an extra entity:
http://www.hibernate.org/hib_docs/reference/en/html/components.html
HTH,
-marina
PLC_David wrote:
> Can you tell me which provider can do this ???
>
>
> David
>
>
>
> Marina Vatkina wrote:
>
>>There is no portable way to support ManyToMany relationships with an extra
>>attribute. Some providers can do it in their own way. For a portable
>>solution,
>>you need to map them as 2 OneToMany relationships with an Entity that
>>represents
>>that extra attribute.
>>
>>Regards,
>>-marina
>>
>>PLC_David wrote:
>>
>>>Hello Gordon,
>>>
>>>I don't understand it :confused:. I've deleted @Entity in the
>>>ShoppingCartPropertiesDTO, but how is the @manytomany
>>>in CustomerDTO ??
>>>
>>>If I have the ShoppingCartPropertiesDTO without the @Entity than I get
>>>following exception:
>>>
>>>Exception Description: Missing descriptor for
>>>[ShoppingCartPropertiesDTO].
>>>Verify that the descriptor has been properly registered with the Session.
>>>
>>>Could you write what you mean, please ?
>>>
>>>
>>>
>>>Gordon Yorke wrote:
>>>
>>>
>>>>Hello,
>>>> Yes you can map the ShoppingCartPropertiesDTO using the @ManyToMany
>>>>annotation. The ShoppingCartPropertiesDTO will have to be marked as an
>>>>Entity. Not marking the ShoppingCartPropertiesDTO as an Entity is most
>>>>likely the cause of the exception you are seeing.
>>>>--Gordon
>>>>
>>>>-----Original Message-----
>>>>From: PLC_David [mailto:spaceman2k4_at_gmx.de]
>>>>Sent: Monday, September 17, 2007 7:12 PM
>>>>To: persistence_at_glassfish.dev.java.net
>>>>Subject: ManyToMany with list of an utility class which contains the
>>>>other objekt fur mapping and an additional attribute
>>>>
>>>>
>>>>
>>>>Hallo, I work with JPA for the first time.
>>>>
>>>>My database:
>>>>
>>>>Customer : ID | NAME | other columns
>>>>Product : ID | DISCRIMINATOR | NAME |other columns | HARDWARE_INTERFACE
>
> |
>
>>>>XML_ID
>>>>Customer_Product_Rel: CUSTOMER_ID | PRODUCT_ID | AMOUNT
>>>>
>>>>My objects:
>>>>
>>>>@Entity
>>>>CustomerDTO: attributes like id, name ... and
>>>>List<ShoppingCartPropertiesDTO> products = new
>>>>ArrayList<ShoppingCartPropertiesDTO>();
>>>>
>>>>ShoppingCartPropertiesDTO: private ProductDTO product = null; private
>>>>Integer amount = null;
>>>>
>>>>@Entity
>>>>@Inheritance(strategy=InheritanceType.SINGLE_TABLE)
>>>>@DiscriminatorColumn(name = "DISCRIMINATOR", discriminatorType =
>>>>DiscriminatorType.STRING, length = 2)
>>>>abstract class Product: id, name ,descr, ...
>>>>
>>>>@Entity(name="SoftwareDTO")
>>>>@DiscriminatorValue("SW")
>>>>public class SoftwareDTO extends ProductDTO: private
>
> SystemRequirementsDTO
>
>>>>systemRequirements = null; private String language = null;
>>>>
>>>>
>>>>My question: Can I map the customer with a list of the additional object
>>>>(ShoppingCartPropertiesDTO) which contains the product and the amount?
>
> And
>
>>>>how is the ManyToMany annotation ?
>>>>
>>>>
>>>>
>>>>An additional question: What means the exception with missing descriptor
>>>>??
>>>>
>>>>Exception Description: Missing descriptor for
>
> [ShoppingCartPropertiesDTO].
>
>>>>Verify that the descriptor has been properly registered with the Session.
>>>> at
>>>>oracle.toplink.essentials.internal.ejb.cmp3.transaction.base.EntityTransactionImpl.commit(EntityTransactionImpl.java:120)
>>>> at
>>>>oracle.toplink.essentials.internal.ejb.cmp3.transaction.EntityTransactionImpl.commit(EntityTransactionImpl.java:60)
>>>> at test.JPATester.runTest2(JPATester.java:186)
>>>>Caused by: Exception [TOPLINK-7009] (Oracle TopLink Essentials - 2.0
>>>>(Build
>>>>b58g-fcs (09/07/2007))):
>>>>oracle.toplink.essentials.exceptions.ValidationException
>>>>
>>>>
>>>>
>>>>Thanks for all posts
>>>>David
>>>>
>>>>
>>>>
>>>>--
>>>>View this message in context:
>>>>http://www.nabble.com/ManyToMany-with-list-of-an-utility-class-which-contains-the-other-objekt-f%C3%BCr-mapping-and-an-additional-attribute-tf4470610.html#a12746960
>>>>Sent from the java.net - glassfish persistence mailing list archive at
>>>>Nabble.com.
>>>>
>>>>
>>>
>>>
>>
>