How to use Transactions in stateless session bean?

[harry]

Totally confused! read article saying how easy it is using the
SessionSynx.... interface - ah can't coz only allowed in stateful beans!

So failing to find anything convincing on the web I'm not sure what to do
now?

I have a stateless session bean (EJB1 - acting as a session facade) that
calls methods on another stateless session bean (EJB2). I want to
encapsulate several EJB2 method calls within a single EJB1 method. This
method does some validation which might result in an exception being thrown
so obviously I'll need to rollback somehow

Do I have to create another session bean, this time make it stateful & put
all methods that require transactions in there? or can I still achieve this
using a stateless bean?

Many thanks - appologies if not correct wording but a bit new to this!

 

[Sudsy]

harry wrote:

Do I have to create another session bean, this time make it stateful & put
all methods that require transactions in there? or can I still achieve this
using a stateless bean?

Many thanks - appologies if not correct wording but a bit new to this!

Look at the container-transaction element nested within the
assembly-descriptor element which is nested in the ejb-jar
element. Here's a brief outline of an ejb-jar.xml file:

<?xml version="1.0"?>
<!DOCTYPE ejb-jar PUBLIC
"-//Sun Microsystems, Inc.//DTD Enterprise JavaBeans 2.0//EN"
"http://java.sun.com/dtd/ejb-jar_2_0.dtd">
<ejb-jar>
<enterprise-beans>
<session>
<ejb-name>MyBean</ejb-name>
<home>com.mine.MyBeanHome</home>
<remote>com.mine.MyBean</remote>
<ejb-class>com.mine.MyBean</ejb-class>
<session-type>Stateless</session-type>
<transaction-type>Container</transaction-type>
</session>
</enterprise-beans>
<assembly-descriptor>
<container-transaction>
<method>
<ejb-name>MyBean</ejb-name>
<method-name>*</method-name>
</method>
<trans-attribute>Required</trans-attribute>
</container-transaction>
</assembly-descriptor>
</ejb-jar>

Looks like you have some reading ahead of you! ;-)

 

[harry]

Thanks Sudsy, I understand that bit but am still confused as to how to use
transaction in stateless session beans? i.e how to start, rollback & commit
them in my code?

cheers

harry

 

[Michael Borgwardt]

Thanks Sudsy, I understand that bit but am still confused as to how to use
transaction in stateless session beans? i.e how to start, rollback & commit
them in my code?

You don't. The container does it for you. Basically, a transacion is started
when the method is called, it is committed when the method completes,
and it's rolled back when the method throws an EJBException or when you call
EJBContext.setRollbackOnly().

 

[harry]

Thanks chaps, got it working now - yippeeeeeeeeeeeeeeeee!