Problem in mapping a many to many relation to a list

Question

Hi,
I have a problem with mapping a many to many relation to a list.
I have a Many to Many relation in my database between tables baskets and products. This relation is implemented with a join table basket_products, which has two fields which correspond to the foreign keys to tables baskets and products. The join table need to have another one column "order", which defines the order of the products for the specific basket.
In my mapping I have:
@Entity
@Table(name = "baskets", uniqueConstraints = {})
public class Components implements java.io.Serializable {
@ManyToMany(cascade = { CascadeType.ALL }, fetch = FetchType.LAZY)
     @JoinTable( name="baskets_products",
                         joinColumns=@JoinColumn(name="b_id", referencedColumnName="pr_id"),
                         inverseJoinColumns=@JoinColumn(name="pr_id", referencedColumnName="pr_id"))
        //This of course doesn't work!!
       //@OrderBy(value="order")
     public List<Products> getProductses() {
          return this.productses;
     public void setProductses(
               List<Products> productses) {
          this.productses = productses;
@Entity
@Table(name = "products", uniqueConstraints = { })
public class Products implements java.io.Serializable {
@ManyToMany(cascade = { CascadeType.ALL }, fetch = FetchType.LAZY, mappedBy = "productses")
     public Set<Baskets> getBasketses() {
          return this.basketses;
     public void setBasketses(Set<Basket> basketses) {
          this.basketses = basketses;
     }In the EJB spec I read that :
"The property or field name must correspond to that of a persistent property or field of the associated
class."
What to do if I want to use a field from the join table to do the ordering of the list??
My problem is that the field "order", is not defined to the EJB container as a persistent field, so it cannot be used. But for my needs it is necessary that this field is included in the join table.
I thought that I could use the secondary table annotation to map the join table to the Baskets class, as well, so that I can define the order field, but this solution seems to me as a really wrong one.
Can anyone help me??
Thanks,
Elenh.

Answer 1

Hi Martin-
Can you please help me. Here are the details:
We have created an AQ in Oracle DB which will have the following message Structure:
CREATE OR REPLACE TYPE enqueue_payload AS OBJECT
( field1 VARCHAR2(100),
field2 VARCHAR2(100),
field3 DATE,
field4 VARCHAR2(100),
field5 NUMBER,
payload CLOB,
In the Payload field we are enqueing an XML message.
We have to use a OSB proxy service to dequeue the message from the AQ, transform it to another format and send to a SOA Composite.
We created a AQ Adapter in Jdeveloper 11g and imported the WSDL, XSD and .jca jca binding file into the OSB project. And configured the OSB proxy service using the WSDL imported.
However in OSB proxy service message flow when I try to create an XQUERY transformation, I see that the Payload field does not expose the structure of the XML message that is being enqueued. I even changed the message structure definition to have the payload field as XMLType. But it didn't help.
On analyzing the XSD created by AQ Adapter, I see that the payload is being defined as "string" in the XSD.
Inputs Needed
=========
1. How can we parse the payload field defined as CLOB/XMLType in OSB so that I can see the structure of the XML message it holds ?
2. Is there any in-built function in OSB to convert it to XML ?
3. Any other inputs in order to transform the XML message coming in the payload field as CLOB/XMLType
Please provide your inputs and I hope that I have clearly explained my use case.
Thanks in advance for your time and help!!
Regards,
Dibya