[cdi-dev] [weld-dev] How to skip CDI injection if a property is not configured in batch application?

[Mark Struberg]

Not possible. The jobs can also only get added at runtime. So you don not have this information during bootstrap.

LieGrue,
strub


> Am 09.03.2015 um 07:39 schrieb Jozef Hartinger <jharting at redhat.com>:
> 
> You can actually work around by listening to ProcessAnnotatedType and removing the @Inject annotation from injection points for which there is no value to inject. Is the set of defined key-value pairs known at the time when the CDI extension is called?
> 
> Jozef
> 
> On 03/09/2015 07:25 AM, Jozef Hartinger wrote:
>> Adding weld-dev.
>> 
>> Hi Cheng,
>> 
>> by defining a producer method you are basically saying "I am able to supply an object for this given type/qualifier combination". There is not way to opt out of it at runtime. Are you concerned about the JVM default values or the default values a user has provided?
>> 
>> Jozef
>> 
>> On 03/07/2015 05:54 PM, Cheng Fang wrote:
>>> Hi Jozef,
>>> 
>>> I'm having a question in using CDI injection in project JBeret (batch impl project), and would appreciate any help from you.
>>> 
>>> A batch application (in Java SE or EE) can inject configured batch properties into batch artifact classes:
>>> 
>>> @Inject
>>> @javax.batch.api.BatchProperty(name = "batchPropName")
>>> String batchPropName = "default name";
>>> 
>>> The property value comes from job.xml, which is the batch job definition descriptor file:
>>> 
>>> <batchlet ref="batchlet1">
>>>         <properties>
>>>                <property name="batchPropName" value="configured name"/>
>>>         </properties>
>>> ...
>>> 
>>> When "batchPropName" property is not configured in job.xml, the injection should not happen, and whatever java default field value should be preserved for batchPropName field.  
>>> 
>>> With our current batch CDI extension [1] and producer bean [2], it injects a null value into this field, overwriting the java default value, when the target batch property is not present.
>>> 
>>> How to signal to Weld to skip performing the injection for those injection targets?  Ideally, I hope it can be done from within producer methods, which is the place we retrieve batch properties and know whether they exist or not.
>>> 
>>> I think this is also how Java EE field injection works.  How do we handle it in EE, and is it something I can mirror?
>>> 
>>> Thanks,
>>> Cheng
>>> 
>>> [1] https://github.com/jberet/jsr352/blob/master/jberet-core/src/main/java/org/jberet/creation/BatchCDIExtension.java
>>> 
>>> [2] https://github.com/jberet/jsr352/blob/master/jberet-core/src/main/java/org/jberet/creation/BatchBeanProducer.java
>>> 
>>> 
>> 
>> 
>> 
>> _______________________________________________
>> weld-dev mailing list
>> 
>> weld-dev at lists.jboss.org
>> https://lists.jboss.org/mailman/listinfo/weld-dev
> 
> _______________________________________________
> weld-dev mailing list
> weld-dev at lists.jboss.org
> https://lists.jboss.org/mailman/listinfo/weld-dev