// Example: given classes A <- B <-C, at OTN A, a proxy c can only pass if no proxy b exists
TraitableBean txBean = (TraitableBean) proxy.getObject();
TraitTypeMap tMap = (TraitTypeMap) txBean._getTraitMap();
Collection<Key<Thing>> x = tMap.immediateParents( this.typeMask );
Key<Thing> k = x.iterator().next();
long originalMask = context.getModificationMask();
if ( ! k.getValue().isTop() ) {
((PropagationContextImpl) context).setModificationMask( -1L );