[jboss-as7-dev] Question about EAR's and Class Loading

[Dimitris Andreadis]

On 22/03/2011 23:28, Carlo de Wolf wrote:
> On 03/22/2011 09:10 PM, Jason T. Greene wrote:
>> On 3/22/11 3:08 PM, Jason T. Greene wrote:
>>> On 3/22/11 2:58 PM, David M. Lloyd wrote:
>>>> On 03/22/2011 02:51 PM, David M. Lloyd wrote:
>>>>> On 03/22/2011 02:42 PM, Andrig Miller wrote:
>>>>>>> If OrderManagerEntities.jar is in the EAR's "lib" directory (or the
>>>>>>> directory you have configured as such in application.xml) then the
>>>>>>> OrderManagerEJB.jar should be able to "see" it. If not then you'll
>>>>>>> need
>>>>>>> an explicit "Class-Path" reference to it from your EJB JAR.
>>>>>> No, my OrderManagerEntities.jar is not the EAR's "lib" directory,
>>>>>> its at the same level as the OrderManagerEJB.jar, and its listed as
>>>>>> an EJB module in the application.xml.
>>>>>>
>>>>>> This seems broken to me.
>>>>> As a rule, we are restricting visibility by default as much as the spec
>>>>> allows (which may mean certain behaviors are different from AS 5/6). So
>>>>> the question is really, is this contrary to spec? If so, it's a bug.
>>>>> That's what we need to answer.
>>>> Here's the relevant passage:
>>>>
>>>> "Components in the EJB container may have access to the following
>>>> classes and resources. Portable applications must not depend on having
>>>> or not having access to these classes or resources.
>>>> [...]
>>>> * The content of any EJB jar files included in the same ear file.
>>>> * The content of any client jar files specified by the above EJB jar
>>>> files."
>>>>
>>>> Thus it is correct to require an explicit Class-Path between EJB JARs
>>>> within an application.
>>> Note that its typically not required if you are using injection / jndi,
>>> because then you are wiring a dependency and passing instances along
>>> module boundaries.
>>>
>>> In the JPA case though, its just local classes, so their needs to be
>>> some kind of import (/lib, class-path ref, module-ref) in our current
>>> low-visibility model.
>> BTW the reason we went with the low-visibility model, was that our
>> thinking was it would reduce CCEs and allow for multiple EJB jars to use
>> different versions of a thirdparty framework in the same EAR.
>>
> I think we should have the option of the high-visibility model. IMO it
> is what users are expecting of the JBoss App Server.

+1

We need also good documentation for this type of changes in behavior.