[EJBTHREE-1659] Support for asynchronous calls on EJB3 in JB

[jaikiran]

Asynchronous invocations on EJB3 beans as explained here http://docs.jboss.org/ejb3/app-server/reference/build/reference/en/html/jboss_extensions.html#d0e427, at present, does not work in JBoss-5.

[java] Exception in thread "main" java.lang.ClassCastException: $Proxy2
 [java] at org.jboss.ejb3.asynchronous.Asynch.getAsynchronousProxy(Asynch.java:38)
 [java] at org.jboss.tutorial.asynch.client.Client.main(Client.java:40)
 [java] Java Result: 1

The ClassCastException arises from this line in org.jboss.ejb3.asynchronous.Asynch.getAsynchronousProxy:

JBossProxy proxy = (JBossProxy)ejbRef;

The proxies that we create in EJB3 on JBoss-5.0, no longer implement this JBossProxy interface and hence this exception. The JNDI tree output of the bean:

+- SomeJNDIName (class: Proxy for: org.jboss.ejb3.core.asynch.test.SimpleSLSBRemote)

The same beans when deployed on JBoss-4.2.x do implement this interface:

+- SimpleSLSB (class: org.jnp.interfaces.NamingContext)
 | +- remote (proxy: $Proxy70 implements interface org.jboss.ejb3.core.asynch.test.SimpleSLSBRemote,interface org.jboss.ejb3.JBossProxy)

Any specific reason why we no longer add this as a default interface for the proxies?

[alrubinger]

"jaikiran" wrote:
Any specific reason why we no longer add this as a default interface for the proxies?

Yes, because "async" should be an optional add-on capability, not something that's baked into the implementation.

There's now a facility within ejb3-common to async-ize *any* object:

http://anonsvn.jboss.org/repos/jbossas/projects/ejb3/trunk/common/src/main/java/org/jboss/ejb3/common/proxy/plugins/async/AsyncUtils.java

Examples of this in use are in the Integration TestSuite, where I refactored the tests to work:

http://anonsvn.jboss.org/repos/jbossas/projects/ejb3/trunk/testsuite/src/test/java/org/jboss/ejb3/test/asynchronous/unit/AsynchronousTestCase.java

S,
ALR

[alrubinger]

Oh also, you might want to differentiate between this JBoss-specific feature and the async mechanism defined by EJB3.1 - this here allows a client to easily spawn off the invocation; 3.1 lets the bean provider denote which methods are eligible for async on the server side.

S,
ALR

[alrubinger]

"ALRubinger" wrote:
Examples of this in use are in the Integration TestSuite, where I refactored the tests to work:

http://anonsvn.jboss.org/repos/jbossas/projects/ejb3/trunk/testsuite/src/test/java/org/jboss/ejb3/test/asynchronous/unit/AsynchronousTestCase.java

And cleaner cases in the Unit Tests for Async Processor:

http://anonsvn.jboss.org/repos/jbossas/projects/ejb3/trunk/common/src/test/java/org/jboss/ejb3/test/common/proxy/unit/AsyncTestCase.java

S,
ALR

[jaikiran]

Thanks, works as documented :)

"ALRubinger" wrote:
Oh also, you might want to differentiate between this JBoss-specific feature and the async mechanism defined by EJB3.1 - this here allows a client to easily spawn off the invocation; 3.1 lets the bean provider denote which methods are eligible for async on the server side.

S,
ALR

Yes, i am going to make a mention of that in the tutorial guide.