How to use FeatureStructure that is not an annotation ?

[Guillaume Vauvert]

Hello,

I want that the jCas contains some information that is not situated in 
the text (so it is not an annotation). This feature structure is a list 
of PersonRef ; each PersonRef contains the ordered list of all 
annotations about a particular person found in the text.
Ex : PersonRef { String firstName=Albert, String lastName=Einstein, 
List<Annotation> annotationList = { Annotation#1(begin=1, end=15, 
text="Albert Einstein"), Annotation#2(begin=101, end=11, "A. Einstein") } }
I have a class EntityRefList : { List<PersonRef> personRefList ; 
List<PlaceRef> placeRefList; }

I believe that EntityRefList should be store in the jCas, so may extend 
org.apache.uima.jcas.cas.TOP.
Is it the good way to do (I should use a standard Annotation, but it is 
not the "UIMA philosophy") ?
If yes, why does JCasGen (the Eclipse tool) seem to wait an Annotation, 
not a org.apache.uima.jcas.cas.TOP ?

Thanks for your help ? Sorry if this kind of question has always be 
sent, I have not found it ...

Guillaume Vauvert