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https://issues.apache.org/jira/browse/FELIX-5802?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16793014#comment-16793014
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David Jencks commented on FELIX-5802:
-------------------------------------

Rob-

The meanings of  framework-singleton and SCR-singleton are rather different.  

framework-singleton means the service implementation object was registered to 
the service registry, so it was eagerly created and can't be changed without 
unregistering the service first.

SCR-singleton usually means that the service implementation object is created 
when the service is first requested and discarded when there are no more uses 
of it. There are exceptions for immediate components and at least in felix SCR 
for components configured to be never discarded after creation.

This difference in behavior means that using framework-singleton for an 
SCR-singleton component is generally wrong.  

framework-bundle means that for each bundle requesting the service, the 
ServiceFactory is asked for a service implementation object; this object is 
cached by the framework per bundle.  What the ServiceFactory returns is up to 
the ServiceFactory, and the framework doesn't care.

Do you have an actual problem to solve related to having something work the way 
you need or are you trying to understand the specs?

> Service Component created via xml defines scope='singleton' and service 
> specifies property with scope='bundle'
> --------------------------------------------------------------------------------------------------------------
>
>                 Key: FELIX-5802
>                 URL: https://issues.apache.org/jira/browse/FELIX-5802
>             Project: Felix
>          Issue Type: Bug
>          Components: Framework
>    Affects Versions: framework-5.6.10
>            Reporter: Matt Pavlovich
>            Priority: Major
>
> Component with scope='singleton' created via xml or annotation has the 
> service registered with a property of service.scope='bundle'
> Project reproducing the issue is available here: 
> [https://github.com/mattrpav/felix-5802] 
> Steps to reproduce:
>  # Define a serviceComponent via xml (or osgi ds annotation)
>  # Deploy bundle
>  # run scr:info (observe Service Scope: singleton)
>  # run service:list (observe service.scope = bundle)
> Investigation:
>  * Service registers with property of 'service.scope=bundle' here: 
> [https://github.com/apache/felix/blob/trunk/framework/src/main/java/org/apache/felix/framework/ServiceRegistrationImpl.java#L327]
>  * Debugging in felix.scr confirms that the xml is being parsed correctly and 
> the returned component metadata shows the 'scope' = 'singleton' correctly 
> [o.a.felix.scr.impl.xml.XmlHandler#L362|https://github.com/apache/felix/blob/trunk/scr/src/main/java/org/apache/felix/scr/impl/xml/XmlHandler.java#L362]
>  * Debugging confirms that felix.scr is detecting DS13 namespace
>  scr:info output:
> {noformat}
> karaf@root()> scr:info TestModule
> *** Bundle: com.foo.test-module (124)
> Component Description:
> Name: BundleModule
> Implementation Class: com.foo.TestModule
> Default State: enabled
> Activation: immediate
> Configuration Policy: optional
> Activate Method: activate
> Deactivate Method: deactivate
> Modified Method: -
> Configuration Pid: [TestModule]
> Services: 
> com.foo.api.Module
> Service Scope: singleton
> Component Description Properties:
> Component Configuration:
> ComponentId: 4
> State: active 
> Component Configuration Properties:
> component.id = 4
> component.name = TestModule{noformat}
> service:list output
> {noformat}
> karaf@root()> service:list
> [com.foo.api.Module]
> ------------------------
> component.id = 4
> component.name = TestModule
> service.bundleid = 124
> service.id = 141 
> service.scope = bundle
> Provided by :
> Company :: Foo :: TestModule (124){noformat}
> OSGI-INF/serviceComponent.xml
> {noformat}
> <?xml version="1.0" encoding="utf-8"?>
> <scr:component xmlns:scr="http://www.osgi.org/xmlns/scr/v1.3.0";      
> name="TestModule" immediate="true">
>     <service scope="singleton">
>         <provide interface="com.foo.api.Module" />
>     </service>
>     <implementation class="com.foo.TestModule" />
> </scr:component>{noformat}
>  
> Note: When the same impl class is reconfigured to register as a service via 
> BundleActivator, the service has a service.scope = 'singleton' 



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