Can someone help me out on two issues I have (ab-)using generics and thus
having type safety issues when implementing UIMA AEs? I am having a hard time
figuring out how to implement an AE without having to resort to "black box"
casts. It seems I am not fully seeing how generics should be applied via the
UIMA API.
1. The first issue is the (superfluous) need to cast an annotation type from
the annotation index. Usually, if I get an iterator, the UIMA tutorials
instruct us to write:
FSIterator<Annotation> annIt = jcas.getAnnotationIndex(myType).iterator();
This is works for non-generic pre-Java 5 code, but because I loose the type
information I supplied to the method fetching the index, I end up with
something like this:
MyAnnotationType ann = (MyAnnotationType) annIt.next();
This is not type safe because of relying on an (both unsafe and unnecessary!)
cast. Can somebody please point out how to create type-safe annotation
iterators? How can I instantiate an iterator other than the (non-generic)
FSIterator<Annotation> in UIMA? Shouldn't there be something more Java-5-like
in the API? E.g.:
FSIterator<MyAnnotationType> =
jcas.getAnnotationTypeIndex(MyAnnotationType.class).iterator();
2. The second type safety issue I have is with external resources. Lets assume
I've got an interface defining a StringMapResource<T>, i.e., much like in the
UIMA tutorials, essentially a Map<String, T> using String keys and some generic
values. Usually, in the initialize(UimaContext ctx) method, I'd write:
StringMapResource<MyType> smr = (StringMapResource<MyType>)
ctx.getResourceObject(myResourceKey);
Obviously, this is not an effective way to implement generics, and the compiler
complains about this unchecked "back box" casting I am doing when fetching the
resource. Is there a type-safe way to initialize resources I am not aware of?
Currently, because of this ugly cast, I even am forced to decorate my
initialize(UimaContext) methods with hideous @SuppressWarnings("unchecked")
annotations and I'd really like to get rid of these "warts". I'd assume there
should be some method to instantiate a type-safe, generic resource factory in
the UIMA API, right?
Thanks for any help!
Florian
--
Florian Leitner, PhD <[email protected]>
Structural Biology and BioComputing Programme
Spanish National Cancer Research Centre (CNIO)
Address: C/ Melchor Fernandez Almagro 3; E-28029 Madrid
Phone: +34 91 732 8000
Fax: +34 91 224 6980
Internet: http://www.cnio.es
