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https://issues.apache.org/jira/browse/FELIX-3963?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13615334#comment-13615334
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Felix Meschberger commented on FELIX-3963:
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After discussion on the list, none of the patches will be applied. Rather we
don't use reflection for InventoryPrinter at all and for ConfigurationPrinter
we support the backwards compatible mechanism of only looking for the method in
the class of the registered service object and expect the method to be public.
The solution to prevent eager API binding is to use dynamic imports and
ServiceFactory as explained in the FAQ
http://felix.apache.org/documentation/tutorials-examples-and-presentations/apache-felix-osgi-faq.html#how-to-provide-optional-services
> Properly handle method resolution through reflection
> ----------------------------------------------------
>
> Key: FELIX-3963
> URL: https://issues.apache.org/jira/browse/FELIX-3963
> Project: Felix
> Issue Type: Bug
> Components: Inventory
> Affects Versions: inventory-1.0.0
> Reporter: Felix Meschberger
> Assignee: Felix Meschberger
> Fix For: inventory-1.0.0
>
> Attachments: FELIX-3963-get.patch, FELIX-3963-search.patch
>
>
> An InventoryPrinter can be registered as an InventoryPrinter service
> implementing the interface or it can be registered as service of any type as
> long as a particular method signature is implemented (along with a number of
> service registration properties required in both cases).
> The method signature is similar to the InventoryPrinter method is:
> void print(String mode, PrinterWriter writer, boolean isZip)
> Previously the ConfigurationPrinter support in Web Console 4.0 supported the
> same mechanism (with a slightly different signature, of course).
> The question is, how is the method found:
> (1) Use the service implementation class only to find any declared method.
> This is how Web Console 4.0 supports ConfigurationPrinter discovery.
> (2) Use the service implementation class hierarchy to find a properly
> declared method. This is the current intent of the InventoryPrinter.
> I think for the backwards compatibility use case (ConfigurationPrinter
> signatures) we should implement the "implementation-class-only" variant (1).
> For new InventoryPrinter services we might consider variant (2). Yet I am not
> sure, whether this really is usefull: Does such a one-off InventoryPrinter
> service really support inheritance and method selection through the class
> hierarchy ? In such cases implementing the InventoryPrinter might make more
> sense.
> See also the discussion at http://felix.markmail.org/thread/rtkogb7uukyt6gky
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