[kepler-dev] seek/kepler conference call notes

[Edward A Lee]

At 10:31 AM 8/25/2004 -0800, Matt Jones wrote:
>Well, two more issues I can see cropping up.
>
>1) We need to make semantic annotations for individual actors, as well as 
>models.  As far as I know there is not a MoML provided for individual 
>actors independently of a model?  How do we annotate, for example, the 
>GarpAlgorithm actor outside of a MoML model so that we can use these 
>annotations in the discovery service?  Should we be providing a standalone 
>MoML for every actor that contains only the actor and its port 
>descriptions, and then attach the 'configure' annotations to that?

I assume here you mean atomic actors, defined in Java.
The key question is where you want the semantic annotation stored.
If it's part of the actor definition, then I would argue that it should
be in the Java file.  This could be done using the same SemanticAnnotation
class that I suggested in my previous email (which extends
ConfigurableAttribute).  The constructor for the actor would
look something like:

    public MyActor extends TypedAtomicActor {
       public MyActor(CompositeEntity container, String name) {
          ...
          semanticAnnotation = new SemanticAnnotation(
                  this, "semanticAnnotation");
          semanticAnnotation.configure(
                  "  ... text for the annotation here ... ");
          ...
       }
       public SemanticAnntation semanticAnnotation;
    }

An advantage of this is that, in effect, the Java file provides
a _default_ semantic annotation, but individual instances could
override it.

Also, it keeps the entire actor definition together in one place.


>2) Some of our actors have a set of ports that are defined and loaded at 
>design time rather than compile time, and are determined by an external 
>source.  For example, the EMLDataSource actor gets its port definitions by 
>reading the metadata about a data source, and the WebService actor gets 
>its port definitions by reading the WSDL document for the service. I had 
>thought that having external annotations would be good because they could 
>be associated with the WSDL or EML rather than the actor itself.  We'll 
>need a way to annotate these dynamically created ports as well as those 
>that are statically defined within an actor.  I envision this to be 
>common.  Another example is instantiating a hypothetical R actor with the 
>ports needed for data flow into and out of a specific R script, rather 
>than using the CommandLine as we currently do (which bypasses all of our 
>typing mechanisms).


If the SemanticAnnotation class is a configurable attribute,
then the same code that creates the ports could create an instance
of SemanticAnnotation contained by the ports.  Would this do the job?

Edward


------------
Edward A. Lee, Professor
518 Cory Hall, UC Berkeley, Berkeley, CA 94720
phone: 510-642-0455, fax: 510-642-2739
eal at eecs.Berkeley.EDU, http://ptolemy.eecs.berkeley.edu/~eal