Hi Frederik,

As Graham says, the way to implement this is with a namespace handler. If you 
create your own namespace then you can add an element (or attribute) in the 
service you want to be intercepted.

The namespace handler can then do something like this:

public Metadata parse(Element elt, ParserContext pc)
    {
        Metadata m = pc.getEnclosingComponent();
        
        ComponentDefinitionRegistry cdr = pc.getComponentDefinitionRegistry();
        
        Interceptor interceptor = getMyInterceptor();

        if(cm instanceof ServiceMetadata)
            cdr.registerInterceptorWithComponent(cm, interceptor);
        else
            throw new RuntimeException("Not a service component");

        return null;
    }

I hope this is helpful, it seems like you're using some pretty advanced 
blueprint, may I ask what it's for?

Tim Ward
-------------------
Apache Aries PMC member & Enterprise OSGi advocate
Enterprise OSGi in Action (http://www.manning.com/cummins)
-------------------


> Date: Fri, 11 Nov 2011 09:20:06 +0000
> Subject: Re: Support for interceptors?
> From: gchart...@gmail.com
> To: user@aries.apache.org
> 
> Hi Frederik,
> 
> The way to get interceptors involved in Blueprint is to add a
> namespace handler.  This is something that processes a blueprint
> namespace extension.  So you would define a namespace that you would
> add to blueprint, and maybe an associated element that you would
> include to identify the services to be intercepted, and then your
> namespace handler would be engaged and have the opportunity to do its
> work.
> 
> Apache Aries has a number of examples of this (e.g. JPA,
> Transactions).  I'd probably start by taking a look at the one for
> transactions: 
> https://svn.apache.org/repos/asf/aries/trunk/transaction/transaction-blueprint/
> 
> I hope this helps.
> 
> Regards, Graham.
> 
> On 10 November 2011 06:48, De Backer Frederik (DBB)
> <frederik.debac...@dexia.com> wrote:
> > Hello all,
> >
> > I am wondering if the OSGi Enterprise specification has some support to
> > define interceptors on OSGi service methods. Suppose for example that I want
> > to log the request parameters of a method, is it possible to define an
> > interceptor in the blueprint.xml method on the service definition. I guess
> > not because I haven't found anything until now. Is there some recommended
> > approach to implement this? For example, by using an AOP framework like
> > aspectj or using spring annotations (however in the last case I don't how
> > how it is possible to define the annotations since I would need another
> > spring-beans.xml file to define my annotations, next to my blueprint.xml
> > file). Has someone done any work on this?
> >
> > Thx a lot for the assistance and kind regards,
> >
> > Frederik.
> >
> > -------------------------------------------------------------------------
> > Dexia disclaimer:
> >
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> > -------------------------------------------------------------------------
> >
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