[cdi-dev] Clarification on 4.3 Specialization

Tomas Remes tremes at redhat.com
Mon Nov 23 02:33:44 EST 2015

Hi Emily,

I am not sure I follow. What is disabled? AlternativeCounterProducerModified? I can see AlternativeCounterProducerModified is enabled in beans.xml of the given bean archive and it means it is selected alternative only per the bean archive. So I can't see any problem (or maybe I don't fully understand). 


----- Original Message -----
From: "Emily Jiang" <emijiang6 at googlemail.com>
To: "cdi-dev" <cdi-dev at lists.jboss.org>
Sent: Sunday, November 22, 2015 10:42:29 PM
Subject: Re: [cdi-dev] Clarification on 4.3 Specialization

any thoughts? 

Should a bean with @Specialize disable a bean even if it is disabled itself? 

On Thu, Nov 19, 2015 at 10:09 AM, Emily Jiang < emijiang6 at googlemail.com > wrote: 

I have an application containing two wars. 


@Inject CounterProducerConsumerModified2 bean; 

containing one bean and an empty-ish beans.xml : 
@Inject at CounterModifiedQualifier String modifiedProducer; 

CounterModifiedQualifier (the interface) 
CounterProducerModified (the bean implementing that interface) 
AlternativeCounterProducerModified (an alternative specialized bean) 

My application failed deployment with the error on Weld but worked on OpenWebBeans 

[ERROR ] CWWKZ0004E: An exception occurred while starting the application testDiffBDA. The exception message was: com.ibm.ws.container.service.state.StateChangeException: org.jboss.weld.exceptions.DeploymentException: WELD-001408: Unsatisfied dependencies for type String with qualifiers @CounterModifiedQualifier 
at injection point [BackedAnnotatedField] @Inject @CounterModifiedQualifier com.ibm.jcdi.test.beansxml.CounterProducerConsumerModified2.modifiedProducer 
at com.ibm.jcdi.test.beansxml.CounterProducerConsumerModified2.modifiedProducer(CounterProducerConsumerModified2.java:0) 

After further investigation and talking to Martin from Weld, the error was caused due to the fact of AlternativeCounterProducerModified disabling the CounterProducerModified bean but itself is not enabled in the jar of beans-xml-modified2.jar. Therefore, no producer is active to produce a bean with the qualifier CounterModifiedQualifier. 

>From Weld's perspective, any bean annotated with @Specialized disables a second bean regardless whether itself is active or not. 

My understanding is that the specialized should only take effect if itself is enabled. Otherwise, we run into the situation of where the specialized bean is not enabled but it disabled another bean. To me, it is wrong. 

I also checked the spec: 
@Alternative @Specializes 
public class MockAsynchronousService extends AsynchronousService { 
When an enabled bean, as defined in Section 5.1.2, “Enabled and disabled beans”, specializes 
a second bean, we can be certain that the second bean is never instantiated or called by the 
container. Even if the second bean defines a producer or observer method, the method will never 
be called. 

The spec says only an enabled bean can specialize a second bean. I would like to know what other people think. 

Emily Jiang 
ejiang at apache.org 

Emily Jiang 
ejiang at apache.org 

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Tomas Remes

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