CMR collections access from web-tier

[zak4899]

Hi,

I've set up a straightfroward one-to-many CMR relationship with two
Entity Beans on JBoss 4 (XDoclet declarations at the end of this post).
Calling the CMR method getAddenda() that returns the Set works
perfectly from another bean, but I would like to call it from custom
JSP tags in the web tier of the same server. When I try this, I get the
following exception:
A CMR collection may only be used within the transction in which it was
created
What do I have to do to call this method from the web tier? A sample
would be great.
Could you point me to documentation explaining this CMR restriction?


Thanks,
blu


In bean Project:
/**
* @ejb.interface-method
*
* @ejb.relation
* name="Project-Addenda"
* role-name="Project-has-many-Addenda"
* target-ejb="Addendum"
* target-role-name="Addendum-belongs-to-Project"
*/
public abstract Set getAddenda();

In bean Addendum:
/**
* @ejb.interface-method
*
* @ejb.relation
* name="Project-Addenda"
* role-name="Addendum-belongs-to-Project"
* target-ejb="Project"
* target-role-name="Project-has-many-Addenda"
* cascade-delete="yes"
*
* @jboss.relation
* related-pk-field="planKey"
* fk-column="plan_key"
* fk-constraint="false"
*/
public abstract ProjectLocal getProject();

[redbeard15]

i'm not sure how you're exactly accessing the various beans n methods, but you mention something that will point to the solution:

Calling the CMR method getAddenda() that returns the Set works
perfectly from another bean, but I would like to call it from custom
JSP tags in the web tier of the same server. When I try this, I get the
following exception:

The act of instantiating a collection of related objects and then retrieving the value objects from that collection must be done in the same transaction.

I suspect that when you call the 'getAddenda()' method from another bean, the methods on that bean require a transaction. You can check your configuration for this.

However, I'm not sure, but I suspect that servlets (e.g., JSP pages) do not wrap entire methods in a transaction. You'll have to do this yourself.

I was running into the same sort of problem running JunitEE tests. I had to augment my JunitEE tests with something like the following (code example not complete):

Context ic = new InitialContext();
tx = (UserTransaction) ic.lookup ("java:comp/UserTransaction");
tx.begin();

AccountLocal lObj = home.findByPrimaryKey(objKey);
AccountValue vObj = lObj.getAccountValue();
tx.commit();

this is because I had created value objects for another bean (1:n) related to Account. sooo, the 'getAccountValue()' method also retrieves value objects for the Account children, all in one method call.

[jelevy01]

RB,

Thank you for your reply, except that I haven't deployed my application yet :(.

I am just tring to get JBoss up w/o exceptions.

J

[jelevy01]

Ignore above, wrong thread.