docs: private static Map<Class<? extends CoreAnnotation>, Set<TreeGraphNode>> getAllDependents(TreeGraphNode node) {
      Map<Class<? extends CoreAnnotation>, Set<TreeGraphNode>> newMap = Generics.newHashMap();
  
      for (Class<?> o : node.label.keySet()) {
        try {
          // The line below will exception unless it's a GrammaticalRelationAnnotation,
          // so the effect is that only the GrammaticalRelationAnnotation things get put into newMap
          o.asSubclass(GrammaticalRelationAnnotation.class);
          newMap.put((Class<? extends CoreAnnotation>) o, (Set<TreeGraphNode>) node.label.get((Class<? extends CoreAnnotation>) o));//javac doesn't compile properly if generics are fully specified (but eclipse does...)
        } catch (Exception e) {
          // ignore a non-GrammaticalRelationAnnotation element
        }
      }
      return newMap;
    }