I found that someone else has encountered this problem
before. In this case it was a
stateless session bean
which created a CMP entity bean A which created 3 other CMP
entity beans in it's ejbStore method.
http://www.mail-archive.com/[email protected]/msg07146.html
My situation is similar I have a business method of a
session bean which is calling
the create methods of
two BMP entity beans is rapid fire fashion. The second entity
bean cannot be created until the first entity bean has
updated the database. My goal
is that the session
bean is a facade object which will guarantee that the entities
are created or rollback them all. Is this an unusual
pattern for EJB when you have
what basically is a
dependent object Entity bean?
Dave
-----Original Message-----
From:
Bolt, Dave [mailto:[EMAIL PROTECTED]]
Sent: Thursday, January 18, 2001 1:33 PM
To: jBoss
Subject: RE: [jBoss-User] BMP and
Container Managed Transactions was "Find er Methods are sl ower when nothing
is returned"
I tried making the changes. I even have tried the following
the session bean is ddc/DocumentLoader and the
entities are ddc/Product and ddc/DocumentVersion. The session bean
has valid ejb-ref entries for the two entity
beans
as well. As I understand it, the declarations below should tell the
container that all of the Home and
Remote interfaces
of all of the Beans require a transaction.
BTW, I am not including any jboss.xml or jaws.xml files in
my EJB jar
Even with all of this, I have no success. The SQL code in
the ejbCreate method of DocumentVersion times out
on
the INSERT statement because the Product record created by the ejbCreate
method of Product has not yet
been committed.
I tried changing the isolation setting in Oracle, but the
driver only supports READ_COMMITTED and SERIALIZABLE,
the default setting being READ_COMMITTED
I agree the EJX tool in JBOSS 2.0 FINAL is buggy. I tend to
do most of the coding of the descriptor by hand.
<assembly-descriptor>
<container-transaction>
<description>Required</description>
<method>
<ejb-name>ddc/DocumentPart</ejb-name>
<method-name>*</method-name>
</method>
<method>
<ejb-name>ddc/Product</ejb-name>
<method-name>*</method-name>
</method>
<method>
<ejb-name>ddc/DocumentPartMedia</ejb-name>
<method-name>*</method-name>
</method>
<method>
<ejb-name>ddc/DocumentLoader</ejb-name>
<method-name>*</method-name>
</method>
<method>
<ejb-name>ddc/DocumentVersion</ejb-name>
<method-name>*</method-name>
</method>
<trans-attribute>Required</trans-attribute>
</container-transaction>
</assembly-descriptor>
-----Original Message-----
From:
Nortje, Andrew [mailto:[EMAIL PROTECTED]]
Sent: Thursday, January 18, 2001 12:13 PM
To:
'jBoss'
Subject: RE: [jBoss-User] BMP and Container
Managed Transactions was "Find er Methods are sl ower when nothing is
returned"
Dave
I think the problem may be in the way you have configured
the transactions in jBoss.
Use the ejx GUI for configuring transactions. I use an older
ejx, the one that comes with jBoss 2.0 FINAL I think is broken or partially
broken.
Make the method on your session bean Required. That way it
will start a transaction if one does not exist and all subsequent operations
will be under that transaction. Make sure other methods, that need to be
part of the same transaction, are also marked Required. I don't believe
jBoss is behaving badly, as I say I have this sort of thing working. Check
your config carefully.
An example of some ejb-jar.xml config for
transactions
<assembly-descriptor>
<container-transaction>
<description>Required</description>
<method>
<ejb-name>Customer</ejb-name>
<method-intf>Home</method-intf>
<method-name>buy</method-name>
<method-params>
<method-param>com.uni.trader.ShoppingCart</method-param>
<method-param>com.uni.account.PaymentDetails</method-param>
</method-params>
</method>
<trans-attribute>Required</trans-attribute>
</container-transaction>
</assembly-descriptor>
-----Original Message-----
From:
Bolt, Dave [mailto:[EMAIL PROTECTED]]
Sent: Thursday, January 18, 2001 11:10 AM
To: jBoss
Subject: RE: [jBoss-User] BMP and
Container Managed Transactions was "Find er Methods are sl ower when nothing
is returned"
I tried changing the beans to reentrant = true. I did have
them marked as non-reentrant. Unfortunately it did not fix the problem. My
create methods are setting all of the attribute data.
Here's the basic issue. It looks like the connection pool is
giving me different connections for each of my beans. As a result the SQL in
the beans is isolated transactionally from the other beans. I guess the
basic question is this. If I have BMP entity beans, running under
container-managed transactions. And if I have beans that have dependency
relationships (For example a foreign-key relationship in the DB) in the
back-end database. How do I write my SQL and connection pool code so that
the beans work properly in the EJB transaction context. Is my only option to
choose a isolation level that allows dirty reads?
How do I set the isolation level in my jboss configuration?
(Since the JBOSS web site is down, I can't look at the docs)
Do I have to do it manually via the Connection
setTransactionIsolation method any time I lookup a connection?
What if I have a mix of BMP, CMP, and (horror) SQL
in a SessionBean?
Thanks
Dave
-----Original Message-----
From: Nortje,
Andrew [mailto:[EMAIL PROTECTED]]
Sent: Thursday, January 18, 2001 10:20 AM
To:
'jBoss'
Subject: RE: [jBoss-User] BMP and Container
Managed Transactions was "Find er Methods are sl ower when nothing is
returned"
Dave
I am doing something similar to what you are and it works
after much struggling i.e. I create and use beans under a single transaction
context. If something fails created rows are rolled back etc.
Anyway I recognize the timeout error, I also had this error.
It turned out I was making reentrant calls to my entity beans and they were
not marked reentrant. You may have a similar problem. Try make your entity
beans reentrant (ejb-jar.xml) then test your code. If it then works then you
are making reentrant calls, you can then take it from there.
Also make sure your create() method correctly populates all
the bean data (attributes), i.e. after create() the bean instance is taken
out the pool and is assigned.
-----Original Message-----
From:
Bolt, Dave [mailto:[EMAIL PROTECTED]]
Sent: Thursday, January 18, 2001 9:21 AM
To: jBoss
Subject: [jBoss-User] BMP and
Container Managed Transactions was "Finder Methods are sl ower when nothing
is returned"
It turns out that it is a database thing, but then again it
isn't. Here's a better description.
I have three EJBs, a session bean and two entity beans. The
entity beans have a one-to-many relationship. If I had EJB 2.0 I would use
the container managed relationship features to handle all of this. Right
now, it's being done the hard way with BMP code. Anyway, the session bean
has a business method marked with a RequiresNew transaction attribute and it
calls the create method of first the master bean and then the entity bean.
In the database (Oracle 8i) the detail records can only exist if the master
record exists (foreign key constraint).
Each of the entity beans obtains a connection from the
connection pool with the following code.
private Connection getConnection()
{
Context ctx = null;
Connection con =
null;
DataSource ds = null;
try
{
ctx = new InitialContext();
ds
= (DataSource)ctx.lookup(JNDINames.DB_POOL);
con = ds.getConnection();
return con;
}
catch(NamingException
ne)
{
System.out.println(ne.getMessage());
System.out.println(ne.getExplanation());
ne.printStackTrace();
throw new EJBException(ne);
}
catch(SQLException
se)
{
System.out.println(se.getMessage());
se.printStackTrace();
throw new EJBException(se);
}
}
The problem that I am having is that the create method of
the master bean is adding records to the database, but the changes are not
visible to the detail bean via it's connection. It could be an isolation
level thing (I haven't found in JBOSS were you set the isolation level for
an Oracle connection pool).
What I want to have happen is that the Session bean will
start a transaction (RequiresNew) which will include the create methods of
the Master and Detail beans (Requires), but it looks like since I am getting
different connections from the connection pool that the ability of the
container to manage the transactions is being
compromised. The error that I finally get in my code is
ORA-02049: timeout: distributed transaction waiting for lock.
Any ideas?
Dave
-----Original Message-----
From:
Cook, Thomas [mailto:[EMAIL PROTECTED]]
Sent: Wednesday, January 17, 2001 6:24 PM
To: 'jBoss'
Subject: RE: [jBoss-User] Finder
Methods are slower when nothing is return ed
Possible a database thing? If nothing is returned,
maybe it is doing a sequential search?
Tom
--
Tom Cook
Systems Development
Australian Submarine
Corporation
Mersey Road
Outer Harbour
+61 8 8348 7645
"From the instant I picked your book up, until the
moment I put it down, I was convulsed with laughter. I fully intend to
read it one day."
- Groucho Marx
-----Original Message-----
From: Bolt, Dave [SMTP:[EMAIL PROTECTED]]
Sent: Thursday, January 18, 2001 5:01 AM
To:
[EMAIL PROTECTED]
Subject: [jBoss-User]
Finder Methods are slower when nothing is returned
I'm trying to write some code to use BMP Entity beans to update an
Oracle 8i database.
I have a session bean that is
doing the data loading from an XML file. I want to use the Entity
bean to see if the data exists (via a Finder method) and
then either create or update the
record depending on
the status.
I am seeing that performance is very
fast if the record already exists, whereas it is very slow if no
records can be found. Has anyone else noticed a difference
in performance in the Finder's thanks
Dave
Bolt
There is always bandwidth, just none for you.
