returns the first and the last of partOfDocument ids that should be covered by this annotation; that is, the begin of this annotation should be at the begin of the first returned part and the end should be the end of the second returned part.
This class expects a MEDLINE structured abstract pointed to by the
PartOfDocument given to the
#parseDocumentPart(VTDNav, PartOfDocument, JCas) method or just plain
text at the XPath location.